Bug 1598021 (CVE-2018-10887)

Summary: CVE-2018-10887 libgit2: integer overflow leads to out-of-bounds read in git_delta_apply, allowing to read before base array
Product: [Other] Security Response Reporter: Riccardo Schirone <rschiron>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: i, icq, igor.raits, security-response-team, veeti.paananen, walter.pete
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: libgit2 0.27.3, libgit2 0.26.5 Doc Type: ---
Doc Text:
It has been discovered that an unexpected sign extension in git_delta_apply function in delta.c file may lead to an integer overflow which in turn leads to an out of bound read, allowing to read before the base object. An attacker may use this flaw to leak memory addresses or cause a Denial of Service.
Story Points: ---
Clone Of: Environment:
Last Closed: 2018-07-11 12:44:45 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: 1599319    
Bug Blocks:    

Description Riccardo Schirone 2018-07-04 07:36:14 UTC
An unexpected sign extension in git_delta_apply function leads to an integer overflow in the bounds check, allowing to bypass it and to read some bytes before the `base` object. An attacker may use this flaw to get an information leak or cause a Denial of Service.

Comment 1 Riccardo Schirone 2018-07-04 07:36:17 UTC
Acknowledgments:

Name: Riccardo Schirone (Product Security Red Hat)

Comment 4 Riccardo Schirone 2018-07-09 13:34:46 UTC
External References:

https://github.com/libgit2/libgit2/releases/tag/v0.27.3

Comment 5 Riccardo Schirone 2018-07-09 13:36:06 UTC
Created libgit2 tracking bugs for this issue:

Affects: fedora-all [bug 1599319]