CVE-2026-10725CWE-409

Protocol::HTTP2 versions before 1.13 for Perl is vulnerable to a HTTP/2 Bomb

High · published June 6, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
34.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00414 · 34.7th percentile
Weakness
CWE-409 · Improper Handling of Highly Compressed Data (Data Amplification)
Published
2026-06-06T09:14Z
EPSS history
Timeline
  • 06 JUN 09:14Z
    Protocol::HTTP2 versions before 1.13 for Perl is vulnerable to a HTTP/2 Bomb
    cvelistv5