High severity · published Oct 26, 2026
CVE-2026-111101
HTTP/1.1 chunked request bodies made of 1-byte chunks amplify memory use in Bandit
New
8.7
CVSS
0.6%
EPSS
No
On KEV
Description
Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/1.1 chunked body reader of mtrudel bandit allows an unauthenticated remote attacker to exhaust server memory and CPU via a request body made of many 1-byte chunks.
The chunked reader in lib/bandit/http1/socket.ex keeps every chunk as its own list cell and binary term until IO.iodata_to_binary/1 joins them, and nothing limits the number of chunks. The :length option of read_body/2 counts only data bytes, so tiny chunks cost far more memory than their payload: 48 MB of 1-byte chunks grew one handler process to about 500 MB and took about 6 s of CPU. The route does not need to read the body, because on keep-alive connections ensure_completed/1 drains unread bodies through the same reader.
This issue affects bandit: from 0.1.0 before 1.14.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
bandit · mtrudel
0.1.0 before 1.14.0; 7201270c34b90f6c9e15c0386c2bb802c0c72ab4 before 220b9dfd27f9a21305be2afc75cbe585ddc24e7a · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-111101
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-111101
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-111101.html
github.com
https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a
github.com
https://github.com/mtrudel/bandit/commit/7201270c34b90f6c9e15c0386c2bb802c0c72ab4
github.com
https://github.com/mtrudel/bandit/security/advisories/GHSA-jwh3-j29h-qfmw
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-111101
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