CVE-2025-43966 [Low] | Security Vulnerability in Libheif

CVE-2025-43966 is rated Low Risk (19.3/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.07%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-05-30	0.27%	0.07%	-0.19%
2	2026-05-29	0.19%	0.27%	+0.07%
3	2026-02-14	—	0.19%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-05-30

0.27%

0.07%

-0.19%

2026-05-29

0.19%

0.27%

+0.07%

2026-02-14

—

0.19%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
2.9	3.1	LOW	`CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. 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:N) Data isn’t meaningfully altered or forged. Availability (A:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	1.4	1.4	[email protected]
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

2.9

3.1

LOW

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

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N): Data isn’t meaningfully altered or forged.
Availability (A:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

1.4

[email protected]

7.5

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

3.6

[email protected]

OS Trackers for CVE-2025-43966

vendor	priority	summary	link
`alpine`	—	CVE-2025-43966: 1 source package rows (libheif); 8 state rows across 3 repos (3.22-community, edge-community, edge-main); fixed 0, open 8.	https://security.alpinelinux.org/vuln/CVE-2025-43966
`debian`	unimportant	CVE-2025-43966 unimportant priority: Debian including 1 source packages (libheif), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2025-43966
`suse`	low	—	https://www.suse.com/security/cve/CVE-2025-43966/
`ubuntu`	medium	CVE-2025-43966 medium priority: Ubuntu including 1 source packages (libheif), 7 status rows across 7 suites (bionic, focal, jammy, noble, oracular, plucky, upstream): not-affected 6, released 1.	https://ubuntu.com/security/CVE-2025-43966

Affected software / configurations for CVE-2025-43966

Vendor	Product	Version	Raw CPE
struktur	libheif	< 1.19.6	cpe:2.3:a:struktur:libheif::::::::

References for CVE-2025-43966

URL	Tags
https://github.com/strukturag/libheif/commit/b38555387e4b5dcf036fe45b0c440aca19b7b69c	Patch
https://github.com/strukturag/libheif/compare/v1.19.5...v1.19.6	Patch Release Notes

URL

CVE-2025-43966

Exploit prediction scoring system (EPSS) score for CVE-2025-43966

Common vulnerability scoring system (CVSS) metrics for CVE-2025-43966

Weakness enumeration for CVE-2025-43966

OS Trackers for CVE-2025-43966

Affected software / configurations for CVE-2025-43966

References for CVE-2025-43966