# CVE-2026-77207: Null Pointer Dereference in PKCS#7 bundle with no certificates

> Unauthenticated remote attackers can crash Libreswan by sending a crafted IKE packet with a PKCS#7 payload containing only CRLs, causing a denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-108033, CLSA-2026-1792158739, DEBIAN-CVE-2026-77207, GHSA-jf6r-wr9w-j67c

## What is CVE-2026-77207?

CVE-2026-77207 is a high-severity vulnerability in The Libreswan Project libreswan, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Libreswan has a null pointer dereference bug in the PKCS#7 handling code for IKE certificate authentication. When libreswan decodes an IKE CERT payload of type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with SEC_PKCS7ContainsCertsOrCrls() and then iterates the certificate list with SEC_PKCS7GetCertificateList(). The two NSS APIs disagree on a SignedData that carries a CRL but no certificates: ContainsCertsOrCrls() returns PR_TRUE (there is a CRL), so the guard passes, but GetCertificateList() returns NULL (there are no certificates). This causes libreswan to dereference a null pointer leading to a crash and restart. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. No remote code execution is possible. Continued exploitation can cause a denial of service.

Weakness: CWE-476 (NULL Pointer Dereference), CWE-252 (Unchecked Return Value)

## Which versions are affected by CVE-2026-77207?


## How do I fix CVE-2026-77207?

Apply the vendor's patch.

## Is CVE-2026-77207 being exploited?

There is no known exploitation of CVE-2026-77207 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-77207 and fix it if it is affected.

What it is: CVE-2026-77207 is a high-severity vulnerability in The Libreswan Project libreswan, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-77207 in the wild and no public exploit code.

Affected product: The Libreswan Project libreswan. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-77207/ (Markdown: https://insights.sbomify.com/CVE-2026-77207/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-77207
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-77207
- OSV: https://osv.dev/vulnerability/CVE-2026-77207

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-77207/
Summaries are generated and may contain mistakes; the official description above is the record.