CVE-2026-56813

Source
https://cve.org/CVERecord?id=CVE-2026-56813
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56813.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-56813
Aliases
Published
2026-07-10T12:51:08.758Z
Modified
2026-08-07T11:31:14.158593126Z
Severity
  • 2.1 (Low) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N CVSS Calculator
Summary
Cookie attribute injection in Plug.Conn.Cookies.encode/2
Details

Improper Neutralization of Parameter/Argument Delimiters vulnerability in elixir-plug plug allows an attacker to inject or override HTTP cookie attributes.

The Plug.Conn.Cookies.encode/2 function in lib/plug/conn/cookies.ex builds the Set-Cookie response header by interpolating the cookie value and its path, domain, same_site, and extra attributes directly into the header without neutralizing the ';' delimiter that separates cookie attributes.

An application that places attacker-controlled data into a cookie value or attribute (for example via Plug.Conn.putrespcookie/4 when reflecting a username or preference) lets an attacker inject a ';' to append or override cookie attributes (such as Domain and Path scope, or dropping the Secure and HttpOnly flags), enabling cookie tossing and session fixation. Carriage return, line feed, and null bytes are rejected by Plug.Conn header validation, so HTTP response splitting is not possible, but attribute injection through ';' is not prevented.

This issue affects plug: from 0.1.0 before 1.16.6, from 1.17.0 before 1.17.4, from 1.18.0 before 1.18.5, from 1.19.0 before 1.19.5, from 1.20.0 before 1.20.3.

Database specific
{
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "0.1.0"
                },
                {
                    "fixed": "1.16.6"
                },
                {
                    "introduced": "1.17.0"
                },
                {
                    "fixed": "1.17.4"
                },
                {
                    "introduced": "1.18.0"
                },
                {
                    "fixed": "1.18.5"
                },
                {
                    "introduced": "1.19.0"
                },
                {
                    "fixed": "1.19.5"
                },
                {
                    "introduced": "1.20.0"
                },
                {
                    "fixed": "1.20.3"
                },
                {
                    "introduced": "f26876aa67aaeb38e616638aa3efbcc2fe2906a5"
                },
                {
                    "fixed": "*"
                }
            ],
            "source": "AFFECTED_FIELD"
        },
        {
            "extracted_events": [
                {
                    "introduced": "0.1.0"
                },
                {
                    "fixed": "1.16.6"
                },
                {
                    "introduced": "1.17.0"
                },
                {
                    "fixed": "1.17.4"
                },
                {
                    "introduced": "1.18.0"
                },
                {
                    "fixed": "1.18.5"
                },
                {
                    "introduced": "1.19.0"
                },
                {
                    "fixed": "1.19.5"
                },
                {
                    "introduced": "1.20.0"
                },
                {
                    "fixed": "1.20.3"
                }
            ],
            "source": "CPE_FIELD"
        },
        {
            "extracted_events": [
                {
                    "introduced": "0.1.0"
                },
                {
                    "fixed": "1.16.6"
                },
                {
                    "introduced": "1.17.0"
                },
                {
                    "fixed": "1.17.4"
                },
                {
                    "introduced": "1.18.0"
                },
                {
                    "fixed": "1.18.5"
                },
                {
                    "introduced": "1.19.0"
                },
                {
                    "fixed": "1.19.5"
                },
                {
                    "introduced": "1.20.0"
                },
                {
                    "fixed": "1.20.3"
                }
            ],
            "source": "DESCRIPTION"
        }
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56813.json",
    "cna_assigner": "EEF",
    "cwe_ids": [
        "CWE-141"
    ]
}
References

Affected packages

Git / github.com/elixir-plug/plug

Affected ranges

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

Affected versions

v0.*
v0.1.0
v0.10.0
v0.11.0
v0.11.1
v0.11.2
v0.11.3
v0.12.0
v0.12.2
v0.13.0
v0.13.1
v0.14.0
v0.2.0
v0.3.0
v0.4.0
v0.4.1
v0.4.2
v0.4.3
v0.4.4
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.6.0
v0.7.0
v0.8.0
v0.8.1
v0.8.2
v0.8.3
v0.8.4
v0.9.0
v1.*
v1.0.0
v1.0.1
v1.0.2
v1.1.0
v1.1.1
v1.1.2
v1.1.3
v1.1.4
v1.10.0
v1.10.1
v1.10.2
v1.10.3
v1.11.0
v1.11.1
v1.12.0
v1.12.1
v1.13.0
v1.13.1
v1.13.2
v1.13.3
v1.13.4
v1.13.5
v1.14.0
v1.14.1
v1.14.2
v1.15.0
v1.15.1
v1.15.2
v1.15.3
v1.16.0
v1.16.1
v1.17.0
v1.18.0
v1.18.1
v1.19.1
v1.2.0
v1.2.0-rc.0
v1.2.1
v1.2.2
v1.20.0
v1.20.1
v1.3.0
v1.3.1
v1.3.2
v1.4.0
v1.4.0-rc.0
v1.4.1
v1.4.2
v1.4.3
v1.5.0
v1.5.0-rc.0
v1.5.0-rc.1
v1.5.0-rc.2
v1.5.1
v1.6.0
v1.6.1
v1.7.0
v1.7.1
v1.7.2
v1.8.0
v1.8.1
v1.8.2
v1.9.0

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56813.json"