Security Resilience

CVE-2026-100118

Crypto Weakness in Adobe C2Pa ≤ 0.91.1

Published
13 October 2026
Modified
17 October 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0036 30th percentile
Risk Priority 57 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). EPSS, Forum of Incident Response and Security Teams (FIRST), epss.first.org. Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-100118 is a high-severity Improper Certificate Validation (CWE-295) vulnerability in Adobe C2Pa. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Masquerading (T1036); ranked at the 30th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-17 (Public Key Infrastructure Certificates) and SC-23 (Session Authenticity) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

CAI Content Credentials is affected by an Improper Certificate Validation vulnerability that could result in a Security feature bypass. An attacker could leverage this vulnerability to bypass security measures and gain unauthorized write access. Exploitation of this issue does not…

more

require user interaction.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

MITRE ATT&CK v20.0

T1036 Masquerading Stealth
Adversaries may attempt to manipulate features of their artifacts to make them appear legitimate or benign to users and/or security tools.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1195 Supply Chain Compromise Initial Access
Adversaries may manipulate products or product delivery mechanisms prior to receipt by a final consumer for the purpose of data or system compromise.
T1195.002 Compromise Software Supply Chain Initial Access
Adversaries may manipulate application software prior to receipt by a final consumer for the purpose of data or system compromise.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
T1495 Firmware Corruption Impact
Adversaries may overwrite or corrupt the flash memory contents of system BIOS or other firmware in devices attached to a system in order to render them inoperable or unable to boot, thus denying the availability to use the devices and/or…
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-100121Same product: Adobe C2Pa
CVE-2026-100123Same product: Adobe C2Pa
CVE-2026-100122Same product: Adobe C2Pa
CVE-2026-100136Same product: Adobe C2Pa
CVE-2026-48442Same product: Adobe C2Pa
CVE-2026-48438Same product: Adobe C2Pa
CVE-2026-95634Same product: Adobe C2Pa
CVE-2026-103296Same product: Adobe C2Pa
CVE-2026-95633Same product: Adobe C2Pa
CVE-2026-103297Same product: Adobe C2Pa

Affected Assets

adobe
c2pa
≤ 0.91.1
adobe
c2pa-web
≤ 0.15.3
adobe
c2patool
≤ 0.28.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 12 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5)

Our mappings, made for this CVE.

PKI certificate issuance and acquisition under an approved policy establishes the trusted roots and processes needed for correct validation.

Protecting session authenticity depends on cryptographic mechanisms whose trust depends on correct certificate validation.

Requiring confidentiality and integrity protection of transmitted data drives use of properly validated certificates in protocols such as TLS.

Mitigating Controls (NIST CSF 2.0)

Our mappings, derived directly from the weakness types (CWEs) cited in the NVD entry via our CWE→CSF cross-walk — links open the control.

PR.AA-03 mostly match
blocks

Certificate-based authentication of users/services/hardware directly depends on correct validation.

PR.DS-02 mostly match
blocks

Proper certificate validation is a core mechanism for protecting data-in-transit confidentiality and integrity.

PR.PS-06 mostly match
blocks

Secure development practices explicitly include implementing correct certificate validation logic.

ID.RA-09 partial match
blocks

Assessing authenticity/integrity of acquired software often relies on code-signing certificate validation.

PR.AA-04 partial match
blocks

Identity assertions conveyed via certificates require validation to be verified.

Mitigating Controls (ISO/IEC 27001:2022 Annex A)

Our mappings, derived directly from the weakness types (CWEs) cited in the NVD entry via our CWE→ISO cross-walk — links open the control.

blocks

Requiring issuance and validation of public-key certificates under an approved policy reduces the chance that certificates with improper validation will be trusted.

finds

A.8.8's reach is DISCLOSURE — it sees only instances that carry a vendor-published flaw. CWE-295 does surface as CVEs (Apple goto fail, Go framework, router firmware, etc.), so the disclosed share is found, but the bulk of certificate-validation defects live in custom first-party code with no published advisory, which is outside A.8.8's reach and belongs to A.8.29.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over our cross-walk; rows rated `none` are excluded, and each rule says how its mapping was checked.

Definition changed on 29 October 2026. Until then this section listed every rule rated above none, partial included. From that date it lists rules whose mapping is rated full or mostly and checked at llm_unverified or higher; partial mappings show when you ask.

Oracle Linux 8 (3 rules)
  • V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. blocks CWE-295
  • V-248531 OL 8, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. blocks CWE-295
  • V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
RHEL 7 (2 rules)
  • V-204447 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
  • V-204448 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
RHEL 8 (2 rules)
  • V-230264 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295

References