Integer overflow in the index.c:read_entry() function while decompressing a compressed prefix length in libgit2 before v0.26.2 allows an attacker to cause a denial of service (out-of-bounds read) via a crafted repository index file.

The remote Ubuntu 14.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8628-1 advisory.

    It was discovered that libgit2 incorrectly handled the Git Smart Protocol. A remote attacker could     possibly use this issue to cause a denial of service or execute arbitrary code. This issue only affected     Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-10128)

    It was discovered that libgit2 incorrectly handled empty packet lines in the Git Smart Protocol. A remote     attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04     LTS and Ubuntu 16.04 LTS. (CVE-2016-10129)

    It was discovered that libgit2 incorrectly handled error reporting in the HTTP transport. A remote     attacker could possibly use this issue to spoof servers. This issue only affected Ubuntu 16.04 LTS.
    (CVE-2016-10130)

    It was discovered that libgit2 incorrectly handled certain crafted ng packets. A remote attacker could     possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu     16.04 LTS, and Ubuntu 18.04 LTS. (CVE-2018-15501)

    Krishna Ram Prakash R and Vivek Parikh discovered that libgit2 incorrectly handled certain repository     index files. A local attacker could possibly use this issue to cause a denial of service. This issue only     affected Ubuntu 18.04 LTS. (CVE-2018-8098)

    Krishna Ram Prakash R and Vivek Parikh discovered that libgit2 incorrectly handled certain repository     index files. A local attacker could possibly use this issue to cause a denial of service. This issue only     affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, and Ubuntu 18.04 LTS. (CVE-2018-8099)

    Micha Majchrowicz and Marcin Wyczechowski discovered that libgit2 incorrectly handled submodule paths. A     remote attacker could possibly use this issue to write files outside the working tree. This issue only     affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-53584)

    Micha Majchrowicz and Marcin Wyczechowski discovered that libgit2 incorrectly handled delta object     result-size headers. A remote attacker could possibly use this issue to cause libgit2 to consume excessive     memory, leading to a denial of service. (CVE-2026-53585)

    Thai Son Dinh discovered that libgit2 incorrectly handled HTTP redirects. A remote attacker could possibly     use this issue to leak credentials to an offsite redirect target. This issue only affected Ubuntu 20.04     LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-53586)

    It was discovered that libgit2 incorrectly handled certain capability buffers in the smart protocol. A     remote attacker could possibly use this issue to cause a denial of service. This issue only affected     Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-53587)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-2936 advisory.

    Multiple vulnerabilities were found in libgit2, a low-level Git library, and are as follows: CVE-2018-8098     Integer overflow in the index.c:read_entry() function while decompressing a compressed prefix length in     libgit2 before v0.26.2 allows an attacker to cause a denial of service (out-of-bounds read) via a crafted     repository index file. CVE-2018-8099 Incorrect returning of an error code in the index.c:read_entry()     function leads to a double free in libgit2 before v0.26.2, which allows an attacker to cause a denial of     service via a crafted repository index file. CVE-2018-10887 It has been discovered that an unexpected sign     extension in git_delta_apply function in delta-apply.c file may lead to an integer overflow which in turn     leads to an out of bound read, allowing to read before the base object. An attacker may use this flaw to     leak memory addresses or cause a Denial of Service. CVE-2018-10888 A missing check in git_delta_apply     function in delta-apply.c file, may lead to an out-of-bound read while reading a binary delta file. An     attacker may use this flaw to cause a Denial of Service. CVE-2018-15501 In ng_pkt in     transports/smart_pkt.c in libgit2, a remote attacker can send a crafted smart-protocol ng packet that     lacks a '\0' byte to trigger an out-of-bounds read that leads to DoS. CVE-2020-12278 path.c mishandles     equivalent filenames that exist because of NTFS Alternate Data Streams. This may allow remote code     execution when cloning a repository. This issue is similar to CVE-2019-1352. CVE-2020-12279 checkout.c     mishandles equivalent filenames that exist because of NTFS short names. This may allow remote code     execution when cloning a repository. This issue is similar to CVE-2019-1353. For Debian 9 stretch, these     problems have been fixed in version 0.25.1+really0.24.6-1+deb9u1. We recommend that you upgrade your     libgit2 packages. For the detailed security status of libgit2 please refer to its security tracker page     at: https://security-tracker.debian.org/tracker/libgit2 Further information about Debian LTS security     advisories, how to apply these updates to your system and frequently asked questions can be found at:
    https://wiki.debian.org/LTS

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
365444	Ubuntu 14.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS : libgit2 vulnerabilities (USN-8628-1)	Nessus	Ubuntu Local Security Checks	Local	critical
159090	Debian DLA-2936-1 : libgit2 - LTS security update	Nessus	Debian Local Security Checks	Local	critical

Detections

Analytics

CVE-2018-8098

medium

Tenable Plugins

critical

critical