VulnerabilityModified
CVE-2021-29921
This (in some situations) allows attackers to bypass access control that is based on IP addresses.
CRITICAL 9.8EPSS 6.88%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (6.88%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In Python before 3,9,5, the ipaddress library mishandles leading zero characters in the octets of an IP address string. This (in some situations) allows attackers to bypass access control that is based on IP addresses.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 6.88% probability · 94th percentile
- CISA KEV
- Not listed
- Affected
- python/python · oracle/communications cloud native core automated test suite · oracle/communications cloud native core binding support function · oracle/communications cloud native core network slice selection function · oracle/graalvm · oracle/zfs storage appliance kit
- Source
- cve@mitre.org
References
- https://bugs.python.org/issue36384Issue Tracking, Patch, Vendor Advisory
- https://docs.python.org/3/library/ipaddress.htmlVendor Advisory
- https://github.com/python/cpython/blob/63298930fb531ba2bb4f23bc3b915dbf1e17e9e1/Misc/NEWS.d/3.8.0a4.rstThird Party Advisory
- https://github.com/python/cpython/pull/12577Patch, Third Party Advisory
- https://github.com/python/cpython/pull/25099Patch, Third Party Advisory
- https://github.com/sickcodesThird Party Advisory
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.mdExploit, Third Party Advisory
- https://python-security.readthedocs.io/vuln/ipaddress-ipv4-leading-zeros.htmlVendor Advisory
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20210622-0003/Third Party Advisory
- https://sick.codes/sick-2021-014Exploit, Third Party Advisory
- https://www.oracle.com//security-alerts/cpujul2021.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
- https://bugs.python.org/issue36384Issue Tracking, Patch, Vendor Advisory
- https://docs.python.org/3/library/ipaddress.htmlVendor Advisory
- https://github.com/python/cpython/blob/63298930fb531ba2bb4f23bc3b915dbf1e17e9e1/Misc/NEWS.d/3.8.0a4.rstThird Party Advisory
- https://github.com/python/cpython/pull/12577Patch, Third Party Advisory
- https://github.com/python/cpython/pull/25099Patch, Third Party Advisory
- https://github.com/sickcodesThird Party Advisory
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.mdExploit, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
- https://python-security.readthedocs.io/vuln/ipaddress-ipv4-leading-zeros.htmlVendor Advisory
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20210622-0003/Third Party Advisory
- https://sick.codes/sick-2021-014Exploit, Third Party Advisory
- https://www.oracle.com//security-alerts/cpujul2021.htmlPatch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.