[pkg-vuln] CVE-2026-59884 in pyasn1@0.6.3 #583

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kert · 2026-08-01T06:01:27Z

kert commented

2026-08-01 06:01:27 +00:00

Severity: HIGH
Package: pyasn1 @ 0.6.3
Fixed in: 0.6.4

pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER decoder shared by the CER and DER codecs parses long-form tags by accumulating continuation octets without an upper bound on the tag ID size, allowing a crafted input to force construction of an arbitrarily large integer with CPU cost growing quadratically and to trigger unhandled ValueError exceptions in Python 3.11+ error formatting paths. Any application decoding untrusted BER, CER, or DER input is affected. This issue is f

Reference: https://nvd.nist.gov/vuln/detail/CVE-2026-59884

**Severity:** HIGH **Package:** `pyasn1` @ `0.6.3` **Fixed in:** `0.6.4` pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER decoder shared by the CER and DER codecs parses long-form tags by accumulating continuation octets without an upper bound on the tag ID size, allowing a crafted input to force construction of an arbitrarily large integer with CPU cost growing quadratically and to trigger unhandled ValueError exceptions in Python 3.11+ error formatting paths. Any application decoding untrusted BER, CER, or DER input is affected. This issue is f **Reference:** https://nvd.nist.gov/vuln/detail/CVE-2026-59884

kert added this to the P21: Package Supply Chain — inventory, mirrors, drift, vuln scanning milestone 2026-08-01 06:01:27 +00:00

kert added the quality ci labels 2026-08-01 06:01:27 +00:00

kert commented

2026-08-13 00:36:16 +00:00

pyasn1 0.6.3→0.6.4. CVE-2026-59884 (unbounded long-form tag accumulation DoS): same exposure analysis as #581 — not attacker-reachable via our usage; fixed upstream in 0.6.4.

Verification: bumped in commit 611a1d6 (pyproject floor raised for the direct dep; transitive pins via uv lock -P; pkg-manifest regenerated). Full test suite green with the bumped packages installed: 14,023 passed / 1 skipped (serial proof run 26m45s, then the commit hook's parallel run 13m58s). tests/api (the JWT/crypto surface) 335 passed post-bump.

pyasn1 0.6.3→0.6.4. CVE-2026-59884 (unbounded long-form tag accumulation DoS): same exposure analysis as #581 — not attacker-reachable via our usage; fixed upstream in 0.6.4. **Verification:** bumped in commit 611a1d6 (pyproject floor raised for the direct dep; transitive pins via `uv lock -P`; pkg-manifest regenerated). Full test suite green with the bumped packages installed: 14,023 passed / 1 skipped (serial proof run 26m45s, then the commit hook's parallel run 13m58s). `tests/api` (the JWT/crypto surface) 335 passed post-bump.

kert closed this issue

2026-08-13 00:36:17 +00:00

kert referenced this issue

2026-08-13 23:42:54 +00:00

[pkg-vuln] CVE-2026-59884 in pyasn1@0.6.3 #604

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Reference: homelab/stack#583