CVE-2023-42503 | Apache Commons Compress: Denial of service via CPU consumption for malformed TAR file

Improper Input Validation, Uncontrolled Resource Consumption vulnerability in Apache Commons Compress in TAR parsing.This issue affects Apache Commons Compress: from 1.22 before 1.24.0. Users are recommended to upgrade to version 1.24.0, which fixes the issue. A third party can create a malformed TAR file by manipulating file modification times headers, which when parsed with Apache Commons Compress, will cause a denial of service issue via CPU consumption. In version 1.22 of Apache Commons Compress, support was added for file modification times with higher precision (issue # COMPRESS-612 [1]). The format for the PAX extended headers carrying this data consists of two numbers separated by a period [2], indicating seconds and subsecond precision (for example “1647221103.5998539”). The impacted fields are “atime”, “ctime”, “mtime” and “LIBARCHIVE.creationtime”. No input validation is performed prior to the parsing of header values. Parsing of these numbers uses the BigDecimal [3] class from the JDK which has a publicly known algorithmic complexity issue when doing operations on large numbers, causing denial of service (see issue # JDK-6560193 [4]). A third party can manipulate file time headers in a TAR file by placing a number with a very long fraction (300,000 digits) or a number with exponent notation (such as “9e9999999”) within a file modification time header, and the parsing of files with these headers will take hours instead of seconds, leading to a denial of service via exhaustion of CPU resources. This issue is similar to CVE-2012-2098 [5]. [1]: https://issues.apache.org/jira/browse/COMPRESS-612 [2]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_05 [3]: https://docs.oracle.com/javase/8/docs/api/java/math/BigDecimal.html [4]: https://bugs.openjdk.org/browse/JDK-6560193 [5]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-2098 Only applications using CompressorStreamFactory class (with auto-detection of file types), TarArchiveInputStream and TarFile classes to parse TAR files are impacted. Since this code was introduced in v1.22, only that version and later versions are impacted.

Published: 2023-09-14 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-42503 is rated Low Risk (35.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.49%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-42503

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.49% +0.44%
2 2025-03-30 0.07% 0.05% -0.02%
3 2025-03-29 0.07%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-42503

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 [email protected]

Weakness enumeration for CVE-2023-42503

GitHub Security Advisory for CVE-2023-42503

GHSA-cgwf-w82q-5jrr · Severity: medium · Ecosystem: maven — Apache Commons Compress denial of service vulnerability

OS Trackers for CVE-2023-42503

vendor priority summary link
debian unimportant CVE-2023-42503 unimportant priority: Debian including 1 source packages (libcommons-compress-java), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2023-42503
redhat medium https://access.redhat.com/security/cve/CVE-2023-42503
suse medium CVE-2023-42503 severity moderate: SUSE including 1 source package names (apache-commons-compress), 13 product×package rows across 13 product lines (SUSE Enterprise Storage 7.1, SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS, … (13 product lines)): Known Not Affected 13. https://www.suse.com/security/cve/CVE-2023-42503/
ubuntu medium CVE-2023-42503 medium priority: Ubuntu including 1 source packages (libcommons-compress-java), 12 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): needs-triage 7, ignored 5. https://ubuntu.com/security/CVE-2023-42503

Affected software / configurations for CVE-2023-42503

Vendor Product Version Raw CPE
apache commons_compress >= 1.22, < 1.24.0 cpe:2.3:a:apache:commons_compress:*:*:*:*:*:*:*:*

References for CVE-2023-42503

cvelogic Threat Intelligence