TI-2026-61862 Aliases CVE-2026-91043

HPACK-indexed cookie fields in Mint HTTP/2 responses bypass max_header_list_size and exhaust client memory

LOW 36CWE-770Published 2026-09-28 · Updated 2026-09-29

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: Present
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

Allocation of Resources Without Limits or Throttling vulnerability in elixir-mint mint allows a malicious HTTP/2 server to exhaust memory on the client host and cause a denial of service. Mint.HTTP2 enforces the client's max_header_list_size setting only on the compressed size of an inbound header block, while RFC 9113 section 6.5.2 defines the limit on the decoded header list. An HPACK indexed field costs one byte on the wire and decodes to a dynamic table entry of up to 4 KB, and join_cookie_headers/1 in lib/mint/http2.ex copies every cookie value of a response into one new binary. A header block under the default 256 KB wire limit therefore makes the client allocate about 1 GB for a single response, and several such responses in one delivery exhaust the memory of the process that owns the connection or of the whole VM. This issue affects mint: from 1.1.0 before 1.10.2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00423 36th percentileScored 2026-11-07

Fix Fixed mint (elixir-mint): 1.10.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
elixir-mint	mint	1.1.0 to before 1.10.2	1.10.2	Patch available	CNA

mint Vendorelixir-mint Affected 1.1.0 to before 1.10.2 Fixed in 1.10.2 Patch available CNA

CPE names CNA · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:elixir-mint:mint::::::::	—	—	—

cpe:2.3:a:elixir-mint:mint:*:*:*:*:*:*:*:* Versions — — ·—

Remediation

Fix · CNA mint (elixir-mint) Fixed in 1.10.2

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-09-28
elixir-mint mint 1.10.2
3 records Highest priority Priority MEDIUM 2 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-63369 Mint HTTP/1 client applies chunked framing when chunked is not the final transfer coding…Priority MEDIUM 61
- TI-2026-62214 Mint HTTP/2 client buffers oversized frames up to 16 MiB before enforcing max_frame_sizePriority MEDIUM 61
Show all 3 records →

Timeline

2026-10-02 Threatist record created from CVE-2026-91043

References

Patch 2

Advisory 1

GitHub Advisory

Other 3

TI-2026-41929 Unauthenticated denial-of-service via unbounded HPACK integer decoding in hpax CVSS 4.0HIGH 8.7
TI-2026-40963 mint buffers an entire chunked response chunk in memory in Mint.HTTP1.decode_body/5 CVSS 4.0HIGH 8.7
TI-2026-36665 HTTP/2 CONTINUATION flood in Mint client via unbounded header-block accumulation CVSS 4.0HIGH 8.2
TI-2026-36126 Unbounded conn.streams growth in Mint HTTP/2 client via unenforced PUSH_PROMISE concurrency CVSS 4.0HIGH 8.2
TI-2026-57046 Unbounded HTTP/1 status-line and chunk-extension buffering in Mint causes memory-exhaustion DoS CVSS 4.0HIGH 8.2
TI-2026-41932 Unbounded HTTP/1 response-header and chunked-trailer accumulation in Mint causes memory-exhaustion DoS CVSS 4.0HIGH 8.2

See all 14 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences