How severe is CVE-2026-31959?

CVE-2026-31959 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-31959?

CVE-2026-31959 affects the following packages: github.com/anchore/quill (Go). Ecosystems affected: Go.

How do I fix CVE-2026-31959?

Update github.com/anchore/quill to 0.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-31959 is resolved across your whole dependency graph.

How do I detect CVE-2026-31959 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/anchore/quill, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-31959 if there is no patch (or I can't update yet)?

Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Is CVE-2026-31959 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-31959 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-31959?

CVE-2026-31959 has an EPSS (Exploit Prediction Scoring System) score of 0.1%, placing it in the 1th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-31959?

CVE-2026-31959 is classified as Server-Side Request Forgery (SSRF) (CWE-918). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-31959 published, and has it been updated?

CVE-2026-31959 was published on March 11, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

MEDIUM severity

CVE-2026-31959 — quill

MEDIUMFix: anchore/quill@e41d66a

CVE-2026-31959 is a medium-severity (CVSS 5.3) Server-Side Request Forgery (SSRF) vulnerability in github.com/anchore/quill. A fix is available for github.com/anchore/quill — see the affected versions and patch details below.

SSRF in Quill via unvalidated URL from Apple notarization log retrieval

Also known asGHSA-7q3q-5px6-4c5pGO-2026-4671

Published

Mar 11, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-31959.

EPSS Exploitation Probability

via FIRST.org ↗

0.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs1th percentile — riskier than 1% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐹github.com/anchore/quill

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Quill before version v0.7.1 contains a Server-Side Request Forgery (SSRF) vulnerability when attempting to fetch the Apple notarization submission logs. Exploitation requires the ability to modify API responses from Apple's notarization service, which is not possible under standard network conditions due to HTTPS with proper TLS certificate validation; however, environments with TLS-intercepting proxies (common in corporate networks), compromised certificate authorities, or other trust boundary violations are at risk.

When retrieving submission logs, Quill fetches a URL provided in the API response without validating that the scheme is https or that the host does not point to a local or multicast IP address. An attacker who can tamper with the response can supply an arbitrary URL, causing the Quill client to issue HTTP or HTTPS requests to attacker-controlled or internal network destinations. This could lead to exfiltration of sensitive data such as cloud provider credentials or internal service responses. Both the Quill CLI and library are affected when used to retrieve notarization submission logs.

Patches

Fixed in Quill version v0.7.1

Workarounds

None

Credit

Anchore would like to thank opera-aklajn (Opera) for reporting this vulnerability

Resources

Apple Get Submission Log API Documentation

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/anchore/quill`	all versions	0.7.1`go get github.com/anchore/quill@v0.7.1`

Affected Products

1 product · 1 configurations

Application

quillanchore

≤ 0.7.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/anchore/quill, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/anchore/quill to 0.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-31959 is resolved across your whole dependency graph.
Workarounds
Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Frequently Asked Questions

### Impact Quill before version `v0.7.1` contains a Server-Side Request Forgery (SSRF) vulnerability when attempting to fetch the Apple notarization submission logs. Exploitation requires the ability to modify API responses from Apple's notarization service, which is not possible under standard network conditions due to HTTPS with proper TLS certificate validation; however, environments with TLS-intercepting proxies (common in corporate networks), compromised certificate authorities, or other trust boundary violations are at risk. When retrieving submission logs, Quill fetches a URL provided