CVEs / CVE-2020-28949
CVE-2020-28949: PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability
- Known exploited in the CISA KEV catalog since 25 Aug 2022
- high 7.8 CVSS 3.1 (NVD)
- EPSS 84.5% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
PEAR Archive_Tar allows an unserialization attack because phar: is blocked but PHAR: is not blocked. PEAR stands for PHP Extension and Application Repository and it is an open-source framework and distribution system for reusable PHP components with known usage in third-party products such as Drupal Core and Red Hat Linux.
Description
Archive_Tar through 1.4.10 has :// filename sanitization only to address phar attacks, and thus any other stream-wrapper attack (such as file:// to overwrite files) can still succeed.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| n/a n/a | n/a | — |
| Product | Affected | Fixed in |
|---|---|---|
| pear/archive_tar (Packagist) | before 1.4.11 | 1.4.11 |
Package versions from GHSA-75c5-f4gw-38r9.
Exploitation
| In CISA KEV since | 25 Aug 2022 |
|---|---|
| Due date for US federal agencies | 15 Sep 2022 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 7.8 highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HScored by NVD |
|---|
References
- CVE-2020-28949 on NVD
- CVE-2020-28949 in the CISA KEV catalog
- https://pear.php.net/bugs/bug.php?id=27002 (cited by CISA)
- https://www.drupal.org/sa-core-2020-013 (cited by CISA)
- https://access.redhat.com/security/cve/cve-2020-28949 (cited by CISA)
- CVE-2020-28949 on OSV
- http://packetstormsecurity.com/files/161095/PEAR-Archive_Tar-Arbitrary-File-Write.html Exploit, Third Party Advisory, VDB Entry
- https://github.com/pear/Archive_Tar/issues/33 Exploit, Issue Tracking, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2020/11/msg00045.html Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/42GPGVVFTLJYAKRI75IVB5R45NYQGEUR/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4V35LBRM6HBCXBVCITKQ4UEBTXO2EG7B/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NBYZSHYTIOBK6V7C4N7TP6KIKCRKLVWP/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VJQQYDAOWHD6RDITDRPHFW7WY6BS3V5N/ Mailing List, Third Party Advisory
- https://security.gentoo.org/glsa/202101-23 Third Party Advisory
- https://www.debian.org/security/2020/dsa-4817 Mailing List, Third Party Advisory
- https://www.drupal.org/sa-core-2020-013 Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-28949 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.