CVE-2026-121727

    Dashboard / Vulnerabilities / CVE-2026-121727

    CVE-2026-121727

    Published: 3 Nov 2026Last Modified: 5 Nov 2026

    Summary: Kore before 4.3.0 Integer Underflow Memory Exhaustion via http_header_recv()

    Details: Kore before 4.3.0 contains an integer underflow vulnerability in HTTP request body handling that allows unauthenticated attackers to bypass http_body_max by sending more body bytes than declared. Attackers can send oversized first segments over many concurrent POST, PUT or DELETE connections, wrapping content_length to grow buffers unbounded and exhaust worker memory.

    References: https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/121xxx/CVE-2026-121727.json, https://kore.io/releases/4.3.0, https://nvd.nist.gov/vuln/detail/CVE-2026-121727, https://www.vulncheck.com/advisories/kore-before-4.3.0-integer-underflow-memory-exhaustion-via-http-header-recv, https://github.com/jorisvink/kore/commit/1ff3c0f6f7973dc7fc8bf38369790ef2d8079b3b, https://github.com/jorisvink/kore, https://github.com/jorisvink/kore/blob/4.3.0-rc5/src/http.c#L934

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- 0
    Fixed -1ff3c0f6f7973dc7fc8bf38369790ef2d8079b3b

    Affected versions

    2.0.0-release

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2026-121727 | CVE-DB