CVE Intelligence
Skip to main content
MEDIUM

CVE-2026-31961

CVE-2026-31961 — Unbounded memory allocation in Quill via unvalidated size fields in Mach-O binary parsing

Quill provides simple mac binary signing and notarization from any platform. Quill before version v0.7.1 contains an unbounded memory allocation vulnerability when parsing Mach-O binaries. Exploitation requires that Quill processes an attacker-supplied Mach-O binary, which is most likely in environments such as CI/CD pipelines, shared signing services, or any workflow where externally-submitted binaries are accepted for signing. When parsing a Mach-O binary, Quill reads several size and count fields from the LC_CODE_SIGNATURE load command and embedded code signing structures (SuperBlob, BlobIndex) and uses them to allocate memory buffers without validating that the values are reasonable or consistent with the actual file size. Affected fields include DataSize, DataOffset, and Size from the load command, Count from the SuperBlob header, and Length from individual blob headers. An…

Published Updated Sources: cvelistV5, GitHub_M

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

0%

chance of exploitation in 30 days

Affects

anchore

quill

CVSS base

5.5

MEDIUM

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

No

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

anchore

Products (1)

quill

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactSource
5.5CVSS 3.1MEDIUM——cvelistV5

Weakness & attack patterns

  • CWE-770

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

  • T1498.001Network Denial of Service: Direct Network Flood
  • T1499Endpoint Denial of Service
  • T1499.003Endpoint Denial of Service: Application Exhaustion Flood

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

  • Search application, proxy, and WAF logs for requests touching /CD.

References

1 on the record

Elsewhere on this site

  • anchoreevery CVE for this vendor
  • CWE-770other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.