CVE-2021-33644
published 2022-08-10CVE-2021-33644: An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname…
PriorityP337high8.1CVSS 3.1
AVNACLPRNUIRSUCHINAH
EPSS
1.13%
63.2th percentile
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
Affected
24 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libtar | < libtar 1.2.20-8+deb12u1 (bookworm) | libtar 1.2.20-8+deb12u1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| feep | libtar | < 1.2.21 | 1.2.21 |
| feep | libtar | — | — |
| feep | libtar | >= 0 < 1.2.20-8+deb12u1~deb11u1 | 1.2.20-8+deb12u1~deb11u1 |
| feep | libtar | >= 0 < 1.2.20-8+deb12u1 | 1.2.20-8+deb12u1 |
| feep | libtar | >= 0 < 1.2.20-8ubuntu0.20.04.1 | 1.2.20-8ubuntu0.20.04.1 |
| feep | libtar | >= 0 < 1.2.20-8ubuntu0.22.04.1 | 1.2.20-8ubuntu0.22.04.1 |
| feep | libtar | >= 0 < 1.2.20-8.1ubuntu0.24.04.1 | 1.2.20-8.1ubuntu0.24.04.1 |
| feep | libtar | >= 0 < 1.2.20-4ubuntu0.1~esm1 | 1.2.20-4ubuntu0.1~esm1 |
| feep | libtar | >= 0 < 1.2.20-7ubuntu0.1~esm1 | 1.2.20-7ubuntu0.1~esm1 |
| msrc | azl3_libtar_1.2.20-11_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_libtar_1.2.20-10_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| msrc | cm1_libtar_1.2.20-10_on_cbl_mariner_1.0 | — | — |
| openatom | openeuler | — | — |
| openatom | openeuler | — | — |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
osv9.1CRITICAL
vendor_ubuntu9.1CRITICAL
vendor_debian8.1HIGH
vendor_msrc8.1HIGH
vendor_redhat8.1HIGH
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Ubuntu
libtar vulnerabilities
vendor_ubuntu·2025-03-31·CVSS 9.1
CVE-2021-33644 [CRITICAL] libtar vulnerabilities
Title: libtar vulnerabilities
Summary: Several security issues were fixed in libtar.
It was discovered that libtar may perform out-of-bounds reads when
processing specially crafted tar files. An attacker could possibly use
this issue to cause libtar to crash, resulting in a denial of service,
or execute arbitrary code. (CVE-2021-33643, CVE-2021-33644)
It was discovered that libtar contained a memory leak due to failing
to free a variable, causing performance degradation. An attacker
could possibly use this issue to cause libtar to crash, resulting in a
denial of service. (CVE-2021-33645, CVE-2021-33646)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
libtar: out-of-bounds read in gnu_longname
vendor_redhat·2022-08-10·CVSS 8.1
CVE-2021-33644 [HIGH] CWE-125 libtar: out-of-bounds read in gnu_longname
libtar: out-of-bounds read in gnu_longname
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
A flaw was found in libtar. This flaw allows an attacker who submits a crafted tar file with size in header struct being 0 to trigger a calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
Package: libtar (Red Hat Enterprise Linux 6) - Out of support scope
Package: libtar (Red Hat Enterprise Linux 7) - Out of support scope
Microsoft
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname causing an out-of-bounds read.
vendor_msrc·2022-08-09·CVSS 8.1
CVE-2021-33644 [HIGH] CWE-125 An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname causing an out-of-bounds read.
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname causing an out-of-bounds read.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect t
Debian
CVE-2021-33644: libtar - An attacker who submits a crafted tar file with size in header struct being 0 ma...
vendor_debian·2021·CVSS 8.1
CVE-2021-33644 [HIGH] CVE-2021-33644: libtar - An attacker who submits a crafted tar file with size in header struct being 0 ma...
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
Scope: local
bookworm: resolved (fixed in 1.2.20-8+deb12u1)
bullseye: resolved (fixed in 1.2.20-8+deb12u1~deb11u1)
OSV
libtar vulnerabilities
osv·2025-03-31·CVSS 9.1
CVE-2021-33643 [CRITICAL] libtar vulnerabilities
libtar vulnerabilities
It was discovered that libtar may perform out-of-bounds reads when
processing specially crafted tar files. An attacker could possibly use
this issue to cause libtar to crash, resulting in a denial of service,
or execute arbitrary code. (CVE-2021-33643, CVE-2021-33644)
It was discovered that libtar contained a memory leak due to failing
to free a variable, causing performance degradation. An attacker
could possibly use this issue to cause libtar to crash, resulting in a
denial of service. (CVE-2021-33645, CVE-2021-33646)
GHSA
GHSA-f326-p7mm-52h2: An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longna
ghsa_unreviewed·2022-08-11
CVE-2021-33644 [HIGH] CWE-125 GHSA-f326-p7mm-52h2: An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longna
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
OSV
CVE-2021-33644: An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longna
osv·2022-08-10·CVSS 8.1
CVE-2021-33644 [HIGH] CVE-2021-33644: An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longna
An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longname, causing an out-of-bounds read.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807https://lists.debian.org/debian-lts-announce/2025/01/msg00026.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S4PJRCJLEAWN2EKXGLSOBTL7O57V7NC/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5YSHZY753R7XW6CIKJVAWI373WW3YRRJ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7Q26QDNOJDOFYWMJWEIK5XR62M2FF6IJ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7WX5YE66CT7Y5C2HTHXSFDKQWYWYWJ2T/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD4HEBSTI22FNYKOKK7W3X6ZQE6FV3XC/https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1807
2022-08-10
Published