{"answers":{"affected":"3 open source packages ship an affected version, including github.com/sigstore/gitsign.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-44309 exists.","fix":"Upgrade github.com/sigstore/gitsign to 0.16.0 or later.","what":"CVE-2026-44309 is a medium-severity vulnerability in sigstore gitsign, published on 15 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-44309 and fix it if it is affected.\n\nWhat it is: CVE-2026-44309 is a medium-severity vulnerability in sigstore gitsign, published on 15 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-44309 exists.\n\nAffected packages and fixed versions:\n- github.com/sigstore/gitsign (Go): affected all versions; fixed in 0.16.0\n- github.com/sigstore/gitsign (Go): affected all versions; fixed in 0.16.0\n- github.com/sigstore/gitsign (Go): affected all versions; fixed in 0.16.0\n\nTask:\n1. 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.\n2. 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.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-44309/ (Markdown: https://insights.sbomify.com/CVE-2026-44309/index.md)","id":"CVE-2026-44309","markdown":"https://insights.sbomify.com/CVE-2026-44309/index.md","name":"CVE-2026-44309","record":{"aliases":["DEBIAN-CVE-2026-44309","GHSA-7rmh-48mx-2vwc","GO-2026-5233","UBUNTU-CVE-2026-44309"],"analysis":{"component_type":"developer_tool","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Git signing tool","requires_auth":"none","summary":"Attackers can craft malformed commits that pass gitsign verification but resolve to different content in git-core, bypassing signature integrity checks.","user_interaction":"required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-347","name":"Improper Verification of Cryptographic Signature"},{"id":"CWE-295","name":"Improper Certificate Validation"}],"description":"Gitsign is a keyless Sigstore to signing tool for Git commits with your a GitHub / OIDC identity. Prior to 0.16.0, gitsign verify and gitsign verify-tag re-encode commit/tag objects through go-git's EncodeWithoutSignature before checking the signature, instead of verifying against the raw git object bytes. For malformed objects with duplicate tree headers, git-core and go-git parse different trees: git-core uses the first, go-git uses the second. A signature crafted over the go-git-normalized form (second tree) passes gitsign verify while git-core resolves the commit to a completely different tree. This breaks the invariant that a verified signature, the commit semantics git-core presents to users, and the object hash logged in Rekor all refer to the same content. This vulnerability is fixed in 0.16.0.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"gitsign verify accepts signatures over go-git-normalized bytes, enabling trust confusion on malformed commits","id":"CVE-2026-44309","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"other","year":"2026"},"n_packages":3,"n_references":1,"next":{"headline":"gitsign --verify panics on empty-certificate PKCS7 and exits 0, bypassing exit-code callers","id":"CVE-2026-44310"},"packages":[{"ecosystem":"Go","fixed":["0.16.0"],"introduced":["0"],"last_affected":[],"package":"github.com/sigstore/gitsign","purl":null,"source":"GHSA-7rmh-48mx-2vwc"},{"ecosystem":"Go","fixed":["0.16.0"],"introduced":["0"],"last_affected":[],"package":"github.com/sigstore/gitsign","purl":"pkg:golang/github.com/sigstore/gitsign","source":"GHSA-7rmh-48mx-2vwc"},{"ecosystem":"Go","fixed":["0.16.0"],"introduced":["0"],"last_affected":[],"package":"github.com/sigstore/gitsign","purl":"pkg:golang/github.com/sigstore/gitsign","source":"GO-2026-5233"}],"prev":{"headline":"Spring Cloud AWS: Missing SNS message signature verification allows spoofing of HTTP/HTTPS endpoint notifications","id":"CVE-2026-44308"},"products":["gitsign"],"published":"2026-05-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-15","vendors":["sigstore"]},"summary":"Attackers can craft malformed commits that pass gitsign verification but resolve to different content in git-core, bypassing signature integrity checks.","url":"https://insights.sbomify.com/CVE-2026-44309/"}