Description
Protocol::HTTP2 versions before 1.13 for Perl is vulnerable to a HTTP/2 Bomb.
Protocol::HTTP2's inbound HPACK path has no header-list size limit, so a small HTTP/2 request can expand into large server memory (the "HTTP/2 bomb").
The headers_decode method materialises a full key+value copy per indexed reference with no running size check, and the stream_header_block_add method appends (since version 1.12) every CONTINUATION frame to the per-stream buffer unbounded.
MAX_HEADER_LIST_SIZE (default 65536) is advertised in SETTINGS but never consulted on decode. It is absent from the decoder and from the :limits export tag.
Metrics
CVSS 3.1 7.5/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| CRUX | Protocol::HTTP2 | < 1.13 |
References
- https://github.com/vlet/p5-Protocol-HTTP2/commit/822bf22224adbd662e8d0b865eeacb2b294d16cd.patchPatch
- https://metacpan.org/release/CRUX/Protocol-HTTP2-1.12/source/lib/Protocol/HTTP2/HeaderCompression.pm#L133Product
- https://metacpan.org/release/CRUX/Protocol-HTTP2-1.12/source/lib/Protocol/HTTP2/Stream.pm#L414Product
- https://metacpan.org/release/CRUX/Protocol-HTTP2-1.13/changesRelease Notes
- https://security.metacpan.org/patches/P/Protocol-HTTP2/1.12/CVE-2026-10725-r2.patchPatch
- http://www.openwall.com/lists/oss-security/2026/06/06/7Mailing List, Third Party Advisory
Timeline
- Published
- Jun 6, 2026
- Last modified
- Jul 23, 2026
- NVD status
- Analyzed