CVE-2026-27654 [High] | Memory Corruption in Nginx Plus

NGINX Open Source and NGINX Plus have a vulnerability in the ngx_http_dav_module module that might allow an attacker to trigger a buffer overflow to the NGINX worker process; this vulnerability may result in termination of the NGINX worker process or modification of source or destination file names outside the document root. This issue affects NGINX Open Source and NGINX Plus when the configuration file uses DAV module MOVE or COPY methods, prefix location (nonregular expression location configuration), and alias directives. The integrity impact is constrained because the NGINX worker process user has low privileges and does not have access to the entire system. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.02%	0.47%	+0.45%
2	2026-03-25	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.02%

0.47%

+0.45%

2026-03-25

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.8	4.0	HIGH	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network. Attack complexity (AC:L) Exploitation conditions are straightforward and stable. Attack requirements (AT:N) No additional preconditions are required beyond normal reachability. Privileges required (PR:N) No privileges are required. User interaction (UI:N) No user interaction is required. Vulnerable system confidentiality impact (VC:N) No confidentiality impact on the vulnerable system. Vulnerable system integrity impact (VI:L) Limited integrity impact on the vulnerable system. Vulnerable system availability impact (VA:H) High availability impact on the vulnerable system. Subsequent system confidentiality impact (SC:N) No confidentiality impact on subsequent systems. Subsequent system integrity impact (SI:N) No integrity impact on subsequent systems. Subsequent system availability impact (SA:N) No availability impact on subsequent systems. Exploit maturity (threat) (E:X) Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked). Confidentiality requirement (CR:X) Not defined: insufficient information; scoring treats this like High (worst case). Integrity requirement (IR:X) Not defined: insufficient information; scoring treats this like High (worst case). Availability requirement (AR:X) Not defined: insufficient information; scoring treats this like High (worst case). Modified attack vector (MAV:X) Not defined: scoring uses the Base Attack Vector (AV). Modified attack complexity (MAC:X) Not defined: scoring uses the Base Attack Complexity (AC). Modified attack requirements (MAT:X) Not defined: scoring uses the Base Attack Requirements (AT). Modified privileges required (MPR:X) Not defined: scoring uses the Base Privileges Required (PR). Modified user interaction (MUI:X) Not defined: scoring uses the Base User Interaction (UI). Modified vulnerable system confidentiality impact (MVC:X) Not defined: scoring uses the Base VC metric. Modified vulnerable system integrity impact (MVI:X) Not defined: scoring uses the Base VI metric. Modified vulnerable system availability impact (MVA:X) Not defined: scoring uses the Base VA metric. Modified subsequent system confidentiality impact (MSC:X) Not defined: scoring uses the Base SC metric. Modified subsequent system integrity impact (MSI:X) Not defined: scoring uses the Base SI metric. Modified subsequent system availability impact (MSA:X) Not defined: scoring uses the Base SA metric. Safety (supplemental) (S:X) Not evaluated. Automatable (supplemental) (AU:X) Not evaluated. Recovery (supplemental) (R:X) Not evaluated. Value density (supplemental) (V:X) Not evaluated. Vulnerability response effort (supplemental) (RE:X) Not evaluated. Provider urgency (supplemental) (U:X) Not evaluated.	—	—	[email protected]
8.2	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:L) Attackers could change some data, but it’s limited—not everything goes. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	4.2	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.8

4.0

HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L): Exploitation conditions are straightforward and stable.
Attack requirements (AT:N): No additional preconditions are required beyond normal reachability.
Privileges required (PR:N): No privileges are required.
User interaction (UI:N): No user interaction is required.
Vulnerable system confidentiality impact (VC:N): No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:L): Limited integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H): High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N): No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N): No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N): No availability impact on subsequent systems.
Exploit maturity (threat) (E:X): Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X): Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X): Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X): Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X): Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X): Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X): Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X): Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X): Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X): Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X): Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X): Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X): Not evaluated.
Automatable (supplemental) (AU:X): Not evaluated.
Recovery (supplemental) (R:X): Not evaluated.
Value density (supplemental) (V:X): Not evaluated.
Vulnerability response effort (supplemental) (RE:X): Not evaluated.
Provider urgency (supplemental) (U:X): Not evaluated.

—

[email protected]

8.2

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:L): Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

4.2

[email protected]

OS Trackers for CVE-2026-27654

vendor	priority	summary	link
`alpine`	—	CVE-2026-27654: 1 source package rows (nginx); 3 state rows across 3 repos (3.22-main, 3.23-main, edge-main); fixed 3, open 0.	https://security.alpinelinux.org/vuln/CVE-2026-27654
`debian`	not yet assigned	CVE-2026-27654 not yet assigned priority: Debian including 1 source packages (nginx), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2026-27654
`redhat`	high	—	https://access.redhat.com/security/cve/CVE-2026-27654
`suse`	high	CVE-2026-27654 severity important: SUSE including 21 source package names (nginx-1.24.0-3.module+el8.10.0+24155+8a5ade52, nginx-1.26.3-2.module+el9.7.0+24173+4204b761.1, …), 21 product×package rows across 3 product lines (SUSE Liberty Linux 8, SUSE Liberty Linux 9, openSUSE Tumbleweed): Fixed 21.	https://www.suse.com/security/cve/CVE-2026-27654/
`ubuntu`	medium	CVE-2026-27654 medium priority: Ubuntu including 1 source packages (nginx), 9 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 4, released 4, not-affected 1.	https://ubuntu.com/security/CVE-2026-27654

Affected software / configurations for CVE-2026-27654

Vendor	Product	Version	Raw CPE
f5	nginx_plus	r32	cpe:2.3:a:f5:nginx_plus:r32:p1::::::
f5	nginx_plus	r32	cpe:2.3:a:f5:nginx_plus:r32:p2::::::
f5	nginx_plus	r32	cpe:2.3:a:f5:nginx_plus:r32:p3::::::
f5	nginx_plus	r32	cpe:2.3:a:f5:nginx_plus:r32:p4::::::
f5	nginx_plus	r33	cpe:2.3:a:f5:nginx_plus:r33:::::::*
f5	nginx_plus	r33	cpe:2.3:a:f5:nginx_plus:r33:p1::::::
f5	nginx_plus	r33	cpe:2.3:a:f5:nginx_plus:r33:p2::::::
f5	nginx_plus	r33	cpe:2.3:a:f5:nginx_plus:r33:p3::::::
f5	nginx_plus	r34	cpe:2.3:a:f5:nginx_plus:r34:::::::*
f5	nginx_plus	r34	cpe:2.3:a:f5:nginx_plus:r34:p1::::::
f5	nginx_plus	r34	cpe:2.3:a:f5:nginx_plus:r34:p2::::::
f5	nginx_plus	r35	cpe:2.3:a:f5:nginx_plus:r35:::::::*
f5	nginx_plus	r35	cpe:2.3:a:f5:nginx_plus:r35:p1::::::
f5	nginx_plus	r36	cpe:2.3:a:f5:nginx_plus:r36:::::::*
f5	nginx_plus	r36	cpe:2.3:a:f5:nginx_plus:r36:p1::::::
f5	nginx_plus	r36	cpe:2.3:a:f5:nginx_plus:r36:p2::::::
f5	nginx_open_source	>= 0.5.13, <= 0.9.7	cpe:2.3:a:f5:nginx_open_source::::::::
f5	nginx_open_source	>= 1.0.0, < 1.28.3	cpe:2.3:a:f5:nginx_open_source::::::::
f5	nginx_open_source	>= 1.29.0, < 1.29.7	cpe:2.3:a:f5:nginx_open_source::::::::

References for CVE-2026-27654

URL	Tags
https://my.f5.com/manage/s/article/K000160382	Vendor Advisory

URL

CVE-2026-27654 | NGINX ngx_http_dav_module vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2026-27654

Common vulnerability scoring system (CVSS) metrics for CVE-2026-27654

Weakness enumeration for CVE-2026-27654

OS Trackers for CVE-2026-27654

Affected software / configurations for CVE-2026-27654

References for CVE-2026-27654