CVE-2017-9047
A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. The variable len is assigned strlen(buf). If the content->type is XML_ELEMENT_CONTENT_ELEMENT, then (i) the content->prefix is appended to buf (if it actually fits) whereupon (ii) content->name is written to the buffer. However, the check for whether the content->name actually fits also uses 'len' rather than the updated buffer length strlen(buf). This allows us to write about "size" many bytes beyond the allocated memory. This vulnerability causes programs that use libxml2, such as PHP, to crash.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 3.19% probability · 87th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-119
- Affected
- xmlsoft/libxml2
- Source
- cve@mitre.org
References
- http://www.debian.org/security/2017/dsa-3952
- http://www.openwall.com/lists/oss-security/2017/05/15/1Exploit, Mailing List, Patch, Third Party Advisory
- http://www.securityfocus.com/bid/98599Third Party Advisory, VDB Entry
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://security.gentoo.org/glsa/201711-01
- http://www.debian.org/security/2017/dsa-3952
- http://www.openwall.com/lists/oss-security/2017/05/15/1Exploit, Mailing List, Patch, Third Party Advisory
- http://www.securityfocus.com/bid/98599Third Party Advisory, VDB Entry
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://security.gentoo.org/glsa/201711-01
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.