PKCS7_verify Certificate Chain Validation Bypass in AWS-LC
Exploitation and risk
Source statusCISA KEV lists vulnerabilities known to be exploited. FIRST EPSS estimates the likelihood of exploitation in the next 30 days. An unavailable score does not mean zero risk.
Which CVEs have scores here?
This view includes predictions for CVE identifiers explicitly listed in public NuGet advisories. Microsoft release pages have their own prediction coverage. Check source status for the scope and latest checks.
No exploitation or prediction data is available here for these CVEs. This does not mean they are safe or unlikely to be exploited.
cve-program · CVE-2026-3336
PublishedImproper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.
- Source published
- 2 Mar 2026 21:15:16 UTC
- Source modified
- 21 Aug 2026 12:13:00 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
euvd · EUVD-2026-9264
PublishedImproper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.
Additional publisher context
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: Mar 2, 2026, 9:15:16 PM
dateUpdated: Aug 21, 2026, 12:13:00 PM
2 related source bulletins · separate from aliases
RHSA-2026:5459: Red Hat Security Advisory: RHTAS 1.3.3 - Red Hat Trusted Artifact Signer Release
CVE-2025-66471 · CVE-2026-3336 · CVE-2026-3338 · CVE-2026-21441 · CVE-2026-31812
msrc_CVE-2026-3336: PKCS7_verify Certificate Chain Validation Bypass in AWS-LC
CVE-2026-3336
- Source published
- Mar 2, 2026, 9:15:16 PM (timezone not stated)
- Source modified
- Aug 21, 2026, 12:13:00 PM (timezone not stated)
- Saved here
- 15 Nov 2026 10:03:08 UTC
- Source terms
- ENISA EUVD · source terms and attribution apply
Original source record · Cite this exact observation · Complete original publisher JSON
Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
EUVD CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
nvd · CVE-2026-3336
PublishedImproper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.
Additional publisher context
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Modified
Weakness classifications: CWE-295
Original publisher date fields
published: 2026-03-02T22:16:31.277
lastModified: 2026-07-15T02:20:59.523
2 source CPE criteria · context only
- cpe:2.3:a:amazon:aws-lc-sys:*:*:*:*:*:rust:*:*
- cpe:2.3:a:amazon:aws_libcrypto:*:*:*:*:*:*:*:*
The original JSON retains the logical configuration operators, exclusions and version bounds.
- Source published
- 2 Mar 2026 22:16:31 UTC
- Source modified
- 15 Jul 2026 02:20:59 UTC
- Saved here
- 25 Oct 2026 08:17:18 UTC
- Source terms
- NIST NVD usage terms; underlying source attribution retained
Original source record · Cite this exact observation · Complete original publisher JSON
Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 4.0 · ff89ba41-3aa1-4d27-914a-91399e9639e5 · Secondary · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/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
CVSS 3.1 · ff89ba41-3aa1-4d27-914a-91399e9639e5 · Secondary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
osv · GHSA-vw5v-4f2q-w9xf
Published### Summary AWS-LC is an open-source, general-purpose cryptographic library. ### Impact Improper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer. Customers of AWS services do not need to take action. aws-lc-sys contains code from AWS-LC. Applications using aws-lc-sys should upgrade to the most recent release of aws-lc-sys. #### Impacted versions: aws-lc-sys versions: >= 0.24.0, < 0.38.0 ### Patches The patch is included in v0.38.0 ### Workarounds There is no workaround. Applications using aws-lc-sys should upgrade to the most recent release of aws-lc-sys. ### Resources If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via the [vulnerability reporting page](https://aws.amazon.com/security/vulnerability-reporting) or directly via email to [[email protected]](mailto:[email protected]). Please do not create a public GitHub issue. ### Acknowledgement AWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.
- Source published
- 3 Mar 2026 20:08:24 UTC
- Source modified
- 10 Sep 2026 03:50:41 UTC
- Saved here
- 24 Oct 2026 13:19:54 UTC
- Source terms
- GitHub Advisory Database · CC-BY-4.0
Original source record · Cite this exact observation · Complete original publisher JSON
Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Publisher rating · HIGH
osv · RUSTSEC-2026-0046
PublishedImproper certificate validation in `PKCS7_verify()` in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer. Customers of AWS services do not need to take action. `aws-lc-sys` contains code from AWS-LC. Applications using `aws-lc-sys` should upgrade to the most recent release of `aws-lc-sys`. There is no workaround; applications using `aws-lc-sys` should upgrade to the most recent release of aws-lc-sys.
- Source published
- 2 Mar 2026 12:00:00 UTC
- Source modified
- 9 Nov 2026 11:00:04 UTC
- Saved here
- 9 Nov 2026 12:02:17 UTC
- Source terms
- OSV · upstream source license applies
Original source record · Cite this exact observation · Complete original publisher JSON
Source: osv · OSV · upstream source license applies. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N