CVE-2025-2866 | PDF signature forgery with adbe.pkcs7.sha1 SubFilter

Improper Verification of Cryptographic Signature vulnerability in LibreOffice allows PDF Signature Spoofing by Improper Validation. In the affected versions of LibreOffice a flaw in the verification code for adbe.pkcs7.sha1 signatures could cause invalid signatures to be accepted as valid This issue affects LibreOffice: from 24.8 before < 24.8.6, from 25.2 before < 25.2.2.

Published: 2025-04-27 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-2866 is rated Low Risk (18.7/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.09%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-2866

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-21 0.01% 0.09% +0.08%
2 2025-04-28 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-2866

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.4 4.0 LOW
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:L/VI:N/VA:N/SC:L/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:L)
Attacker needs local access on the target system.
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:L)
Low privileges are required.
User interaction (UI:P)
A user has to participate (for example click/open/approve).
Vulnerable system confidentiality impact (VC:L)
Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:L)
Limited 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]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N 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: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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2025-2866

OS Trackers for CVE-2025-2866

vendor priority summary link
alpine low CVE-2025-2866: 1 source package rows (libreoffice); 7 state rows across 1 repos (edge-community); fixed 0, open 7. https://security.alpinelinux.org/vuln/CVE-2025-2866
debian not yet assigned CVE-2025-2866 not yet assigned priority: Debian including 1 source packages (libreoffice), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-2866
redhat low — https://access.redhat.com/security/cve/CVE-2025-2866
suse medium CVE-2025-2866 severity moderate: SUSE including 146 source package names (libreoffice, libreoffice-base, …), 618 product×package rows across 5 product lines (SUSE Linux Enterprise Module for Package Hub 15 SP6, SUSE Linux Enterprise Module for Package Hub 15 SP7, … (5 product lines)): Known Not Affected 618. https://www.suse.com/security/cve/CVE-2025-2866/
ubuntu medium CVE-2025-2866 medium priority: Ubuntu including 1 source packages (libreoffice), 6 status rows across 6 suites (focal, jammy, noble, oracular, plucky, upstream): released 5, not-affected 1. https://ubuntu.com/security/CVE-2025-2866

Affected software / configurations for CVE-2025-2866

Vendor Product Version Raw CPE
libreoffice libreoffice >= 24.8.0.1, < 24.8.6.0 cpe:2.3:a:libreoffice:libreoffice:*:*:*:*:*:*:*:*
libreoffice libreoffice >= 25.2.0.1, < 25.2.2 cpe:2.3:a:libreoffice:libreoffice:*:*:*:*:*:*:*:*
libreoffice libreoffice 24.8.0.0 cpe:2.3:a:libreoffice:libreoffice:24.8.0.0:alpha1:*:*:*:*:*:*
libreoffice libreoffice 24.8.0.0 cpe:2.3:a:libreoffice:libreoffice:24.8.0.0:beta1:*:*:*:*:*:*
libreoffice libreoffice 25.2.0.0 cpe:2.3:a:libreoffice:libreoffice:25.2.0.0:alpha1:*:*:*:*:*:*
libreoffice libreoffice 25.2.0.0 cpe:2.3:a:libreoffice:libreoffice:25.2.0.0:beta1:*:*:*:*:*:*

References for CVE-2025-2866

cvelogic Threat Intelligence