vulnwire
7.5high

CVE-2017-9047

A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801.

Published 9 y ago · modified 24 d ago · JSON

CVSS
7.5
v3.0 · NVD
CISA KEV
No
not known exploited
EPSS
3.2%
percentile 88%
Public exploits
0
none known

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.

Exploit prediction (EPSS)

3.16% probability of exploitation in the next 30 days, higher than 88% of all scored CVEs.

CVSS scores

Assigned byVersionScoreVector
NVD3.07.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD2.05.0AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

  • securityfocus.com /bid/98599 · vdb-entry, x_refsource_BID, x_transferred
  • debian.org /security/2017/dsa-3952 · vendor-advisory, x_refsource_DEBIAN, x_transferred
  • security.gentoo.org /glsa/201711-01 · vendor-advisory, x_refsource_GENTOO, x_transferred
  • openwall.com /lists/oss-security/2017/05/15/1 · x_refsource_MISC, x_transferred
  • lists.apache.org /thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkee · mailing-list, x_refsource_MLIST, x_transferred
  • lists.apache.org /thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkee · mailing-list, x_refsource_MLIST, x_transferred
  • cert-portal.siemens.com /productcert/html/ssa-398330.html

Sources

vulnwire keeps one entry per vulnerability: the CVE id wins, then GHSA; records that alias each other are merged. Machine-readable: JSON.