Article Detail

Product Affected

This issue affects all versions of Junos OS.

Severity

Critical

Severity Assessment (CVSS) Score

9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Problem

Multiple vulnerabilities in the third party software component expat have been resolved.

This issue affects Juniper Networks Junos OS:

All versions prior to 19.1R3-S10;

19.4 versions prior to 19.4R3-S10;

20.2 versions prior to 20.2R3-S6;

20.3 versions prior to 20.3R3-S6;

20.4 versions prior to 20.4R3-S5;

21.1 versions prior to 21.1R3-S4;

21.2 versions prior to 21.2R3-S4;

21.3 versions prior to 21.3R3-S3;

21.4 versions prior to 21.4R3-S1;

22.1 versions prior to 22.1R2-S2, 22.1R3;

22.2 versions prior to 22.2R2-S1, 22.2R3.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was discovered during external security research.

Important security issues resolved include:

CVE	CVSS	Summary
CVE-2021-45960	8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)	In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).
CVE-2021-46143	7.8 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)	In doProlog in xmlparse.c in Expat (aka libexpat) before 2.4.3, an integer overflow exists for m_groupSize.
CVE-2022-22822	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	addBinding in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-22823	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	build_model in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-22824	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	defineAttribute in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-22825	8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)	lookup in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-22826	8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)	nextScaffoldPart in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-22827	8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)	storeAtts in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
CVE-2022-23852	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	Expat (aka libexpat) before 2.4.4 has a signed integer overflow in XML_GetBuffer, for configurations with a nonzero XML_CONTEXT_BYTES.
CVE-2022-23990	7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)	Expat (aka libexpat) before 2.4.4 has an integer overflow in the doProlog function.
CVE-2022-25235	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a UTF-8 character is valid in a certain context.
CVE-2022-25236	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	xmlparse.c in Expat (aka libexpat) before 2.4.5 allows attackers to insert namespace-separator characters into namespace URIs.
CVE-2022-25313	6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H)	In Expat (aka libexpat) before 2.4.5, an attacker can trigger stack exhaustion in build_model via a large nesting depth in the DTD element.
CVE-2022-25314	7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)	In Expat (aka libexpat) before 2.4.5, there is an integer overflow in copyString.
CVE-2022-25315	9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)	In Expat (aka libexpat) before 2.4.5, there is an integer overflow in storeRawNames.

Solution

The following software releases have been updated to resolve this specific issue: 19.4R3-S10, 20.2R3-S6, 20.3R3-S6, 20.4R3-S5, 21.1R3-S4, 21.2R3-S4, 21.3R3-S3, 21.4R3-S1, 22.1R2-S2, 22.1R3, 22.2R2-S1, 22.2R3, 22.3R1, 22.3R1-S1, 22.3R2, 22.4R1, and all subsequent releases.

This issue is being tracked as 1688079

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).

Workaround

To reduce the risk of exploitation of these issues, use access lists or firewall filters to limit access to only trusted administrative networks, hosts and users.

Severity Assessment

Information for how Juniper Networks uses CVSS can be found at KB 16446 [juniper.net] "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories.

Modification History