Bug 2218122 (CVE-2023-2860, ZDI-23-692, ZDI-CAN-18511)

Summary: CVE-2023-2860 kernel: ipv6: sr: out-of-bounds read when setting HMAC data
Product: [Other] Security Response Reporter: Mauro Matteo Cascella <mcascell>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: acaringi, allarkin, bhu, chwhite, crwood, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: kernel 6.0-rc5 Doc Type: ---
Doc Text:
An out-of-bounds read vulnerability was found in the SR-IPv6 implementation in the Linux kernel. The flaw exists within the processing of seg6 attributes. The issue results from the improper validation of user-supplied data, which can result in a read past the end of an allocated buffer. This flaw allows a privileged local user to disclose sensitive information on affected installations of the Linux kernel.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2023-06-28 10:59:49 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2218114    

Description Mauro Matteo Cascella 2023-06-28 08:48:08 UTC 
An out-of-bounds read vulnerability was found in the SR-IPv6 implementation in the Linux kernel. Quoting ZDI security advisory [1]:

"This vulnerability allows local attackers to disclose sensitive information on affected installations of the Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability.

The specific flaw exists within the processing of seg6 attributes. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated buffer. An attacker can leverage this in conjunction with other vulnerabilities to escalate privileges and execute arbitrary code in the context of the kernel."

[1] https://www.zerodayinitiative.com/advisories/ZDI-CAN-18511/
Comment 1 Mauro Matteo Cascella 2023-06-28 08:48:27 UTC 
Upstream fix:
https://github.com/torvalds/linux/commit/84a5358