CVE-2026-55951

Source
https://cve.org/CVERecord?id=CVE-2026-55951
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55951.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-55951
Aliases
Downstream
Published
2026-09-01T14:37:02.650Z
Modified
2026-09-03T03:48:18.857585205Z
Severity
  • 8.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
httpc memory exhaustion via unbounded response header accumulation
Details

The Erlang/OTP httpc HTTP client does not enforce a limit on the total size of response headers received from a server. The maxheadersize option defaults to nolimit, and httpcresponse:parseheaders/6 accumulates every header into a list before the length check runs (which only fires after the terminating CRLF CRLF is received).

A malicious or compromised HTTP server can send an arbitrarily large number of headers, or headers with very large values, causing the client process to allocate unbounded memory until the system runs out of memory or the BEAM VM crashes. A proof-of-concept server sending 100,000 headers of roughly 4000 bytes each caused the client VM to allocate over 13 GB of memory in under 30 seconds.

Any application using httpc:request/4,5 to connect to untrusted servers is affected. No authentication is required: any server the client connects to (including via a redirect or man-in-the-middle) can trigger the exhaustion.

This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.

Database specific
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55951.json",
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "introduced": "17.0"
                },
                {
                    "fixed": "27.3.4.17"
                },
                {
                    "introduced": "28.0"
                },
                {
                    "fixed": "28.5.0.6"
                },
                {
                    "introduced": "29.0"
                },
                {
                    "fixed": "29.0.6"
                },
                {
                    "introduced": "5.10"
                },
                {
                    "fixed": "9.3.2.7"
                },
                {
                    "introduced": "9.4"
                },
                {
                    "fixed": "9.6.2.3"
                },
                {
                    "introduced": "9.7"
                },
                {
                    "fixed": "9.7.2"
                },
                {
                    "introduced": "84adefa331c4159d432d22840663c38f155cd4c1"
                },
                {
                    "fixed": "*"
                }
            ]
        },
        {
            "source": "CPE_FIELD",
            "extracted_events": [
                {
                    "fixed": "27.3.4.17"
                },
                {
                    "introduced": "28.0"
                },
                {
                    "fixed": "28.5.0.6"
                },
                {
                    "introduced": "29.0"
                },
                {
                    "fixed": "29.0.6"
                }
            ]
        },
        {
            "source": "DESCRIPTION",
            "extracted_events": [
                {
                    "introduced": "17.0"
                },
                {
                    "introduced": "28.0"
                },
                {
                    "introduced": "29.0"
                },
                {
                    "introduced": "5.10"
                },
                {
                    "fixed": "9.3.2.7"
                },
                {
                    "introduced": "9.4"
                },
                {
                    "fixed": "9.6.2.3"
                },
                {
                    "introduced": "9.7"
                },
                {
                    "fixed": "9.7.2"
                },
                {
                    "fixed": "5.10"
                }
            ]
        }
    ],
    "cna_assigner": "EEF",
    "cwe_ids": [
        "CWE-770"
    ]
}
References

Affected packages

Git / github.com/erlang/otp

Affected ranges

Type
GIT
Repo
https://github.com/erlang/otp
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
Fixed
Database specific
Show details
{
    "source": "REFERENCES"
}

Affected versions

OTP-17.*
OTP-17.0
OTP-18.*
OTP-18.0
OTP-18.0-rc1
OTP-19.*
OTP-19.0
OTP-19.0-rc1
OTP-19.0-rc2
OTP-20.*
OTP-20.0
OTP-20.0-rc1
OTP-20.0-rc2
OTP-21.*
OTP-21.0
OTP-21.0-rc1
OTP-21.0-rc2
OTP-22.*
OTP-22.0
OTP-22.0-rc1
OTP-22.0-rc2
OTP-22.0-rc3
OTP-23.*
OTP-23.0
OTP-23.0-rc1
OTP-23.0-rc2
OTP-23.0-rc3
OTP-24.*
OTP-24.0
OTP-24.0-rc1
OTP-24.0-rc2
OTP-24.0-rc3
OTP-25.*
OTP-25.0
OTP-25.0-rc1
OTP-25.0-rc2
OTP-25.0-rc3
OTP-26.*
OTP-26.0
OTP-26.0-rc1
OTP-26.0-rc2
OTP-26.0-rc3
OTP-27.*
OTP-27.0
OTP-27.0-rc1
OTP-27.0-rc2
OTP-27.0-rc3
OTP-27.1
OTP-27.2
OTP-27.3
OTP-27.3.1
OTP-27.3.2
OTP-27.3.3
OTP-27.3.4
OTP-28.*
OTP-28.0
OTP-28.0-rc1
OTP-28.0-rc2
OTP-28.0-rc3
OTP-28.0-rc4
OTP-28.1
OTP-28.4
OTP-28.5
OTP_17.*
OTP_17.0-rc1
OTP_17.0-rc2
Other
OTP_R13B03
OTP_R13B04
OTP_R14A
OTP_R14B
OTP_R14B01
OTP_R14B02
OTP_R14B03
OTP_R15A
OTP_R15B
OTP_R16A_RELEASE_CANDIDATE
OTP_R16B
patch-base-27
patch-base-28

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55951.json"