{"cve":"CVE-2026-48702","nvd":{"published":"2026-08-13T14:17:01.427","modified":"2026-10-23T18:10:00.167","status":"Awaiting Analysis","description":"Rekor is a software supply chain transparency log. Starting in version 0.3.0 and prior to version 1.5.2, the `Package.Unmarshal()` function in `pkg/types/alpine/apk.go` decompresses the signature and control gzip members of an APK file into in-memory buffers without bounding the total decompressed size. The existing `max_apk_metadata_size` check (default 1MB) is only applied to individual tar entry header sizes after decompression completes, so it does not prevent a decompression bomb from consuming unbounded heap memory. An attacker can craft a gzip stream that compresses at a ~1000:1 ratio (e.g., 2MB compressed zeros → 2GB decompressed). When submitted as spec.package.content in an Alpine `ProposedEntry`, the server decompresses the full payload into memory during request processing, triggering a fatal Go runtime out-of-memory error or OS OOM-kill that cannot be caught by the server's recover() middleware. This is reachable via two unauthenticated endpoints, `POST /api/v1/log/entries (createLogEntry)` and `POST /api/v1/log/entries/retrieve (searchLogQuery)`. Both invoke `V001Entry.Canonicalize()` → `fetchExternalEntities()` → `apk.Unmarshal(packageData)`, which performs the unbounded decompression. Version 1.5.2 patches the issue. There is no effective workaround. Setting `max_request_body_size` reduces but does not eliminate exposure due to the ~1000:1 compression ratio (a 1MB body limit still allows ~1GB heap allocation). Setting `max_apk_metadata_size` has no effect on this vulnerability since the check is applied after decompression.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-770"],"references":["https://github.com/sigstore/rekor/security/advisories/GHSA-47q9-m4ww-924m"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:35.584907681+00:00"},"epss":{"cve":"CVE-2026-48702","score":0.0046,"percentile":0.396,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-47q9-m4ww-924m","url":"https://osv.dev/vulnerability/GHSA-47q9-m4ww-924m","summary":"Rekor has an OOM Condition due to Unbounded gzip Decompression in Alpine APK Parsing Logic","modified":"2026-09-10T03:51:07.818604249Z","packages":[{"ecosystem":"Go","name":"github.com/sigstore/rekor","purl":"pkg:golang/github.com/sigstore/rekor","ranges":[">=0.3.0 <1.5.2"],"fixed":["1.5.2"]}]},{"id":"GO-2026-5778","url":"https://osv.dev/vulnerability/GO-2026-5778","summary":"Rekor has an OOM Condition due to Unbounded gzip Decompression in Alpine APK Parsing Logic in github.com/sigstore/rekor","modified":"2026-07-08T15:29:22.973101404Z","packages":[{"ecosystem":"Go","name":"github.com/sigstore/rekor","purl":"pkg:golang/github.com/sigstore/rekor","ranges":[">=0.3.0 <1.5.2"],"fixed":["1.5.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}