CVE-2016-7952

X.org libXtst before 1.2.3 allows remote X servers to cause a denial of service (infinite loop) via a reply in the (1) XRecordStartOfData, (2) XRecordEndOfData, or (3) XRecordClientDied category without a client sequence and with attached data.

X.org libXtst before 1.2.3 allows remote X servers to cause a denial of service (infinite loop) via a reply in the (1) XRecordStartOfData, (2) XRecordEndOfData, or (3) XRecordClientDied category without a client sequence and with attached data.

X.org libXtst before 1.2.3 allows remote X servers to cause a denial of service (infinite loop) via a reply in the (1) XRecordStartOfData, (2) XRecordEndOfData, or (3) XRecordClientDied category without a client sequence and with attached data.

The XvQueryAdaptors and XvQueryEncodings functions in X.org libXv before 1.0.11 allow remote X servers to trigger out-of-bounds memory access operations via vectors involving length specifications in received data (CVE-2016-5407).

The XGetImage function in X.org libX11 before 1.6.4 might allow remote X servers to gain privileges via vectors involving image type and geometry, which triggers out-of-bounds read operations (CVE-2016-7942).

The XListFonts function in X.org libX11 before 1.6.4 might allow remote X servers to gain privileges via vectors involving length fields, which trigger out-of-bounds write operations (CVE-2016-7943).

Integer overflow in X.org libXfixes before 5.0.3 on 32-bit platforms might allow remote X servers to gain privileges via a length value of INT_MAX, which triggers the client to stop reading data and get out of sync (CVE-2016-7944).

Multiple integer overflows in X.org libXi before 1.7.7 allow remote X servers to cause a denial of service (out-of-bounds memory access or infinite loop) via vectors involving length fields (CVE-2016-7945).

X.org libXi before 1.7.7 allows remote X servers to cause a denial of service (infinite loop) via vectors involving length fields (CVE-2016-7946).

Multiple integer overflows in X.org libXrandr before 1.5.1 allow remote X servers to trigger out-of-bounds write operations via a crafted response (CVE-2016-7947).

X.org libXrandr before 1.5.1 allows remote X servers to trigger out-of-bounds write operations by leveraging mishandling of reply data (CVE-2016-7948).

Multiple buffer overflows in the XvQueryAdaptors and XvQueryEncodings functions in X.org libXrender before 0.9.10 allow remote X servers to trigger out-of-bounds write operations via vectors involving length fields (CVE-2016-7949).

The XRenderQueryFilters function in X.org libXrender before 0.9.10 allows remote X servers to trigger out-of-bounds write operations via vectors involving filter name lengths (CVE-2016-7950).

Multiple integer overflows in X.org libXtst before 1.2.3 allow remote X servers to trigger out-of-bounds memory access operations by leveraging the lack of range checks (CVE-2016-7951).

X.org libXtst before 1.2.3 allows remote X servers to cause a denial of service (infinite loop) via a reply in the XRecordStartOfData, XRecordEndOfData, or XRecordClientDied category without a client sequence and with attached data (CVE-2016-7952).

Buffer underflow in X.org libXvMC before 1.0.10 allows remote X servers to have unspecified impact via an empty string (CVE-2016-7953).

This update for the X Window System client libraries fixes a class of privilege escalation issues.

A malicious X Server could send specially crafted data to X clients, which allowed for triggering crashes, or privilege escalation if this relationship was untrusted or crossed user or permission level boundaries.

libX11, libXfixes, libXi, libXrandr, libXrender, libXtst, libXv, libXvMC were fixed, specifically:

libX11:

• CVE-2016-7942: insufficient validation of data from the X server allowed out of boundary memory read (bsc#1002991)

libXfixes:

• CVE-2016-7944: insufficient validation of data from the X server can cause an integer overflow on 32 bit architectures (bsc#1002995)

libXi:

• CVE-2016-7945, CVE-2016-7946: insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service) (bsc#1002998)

libXtst:

• CVE-2016-7951, CVE-2016-7952: insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service) (bsc#1003012)

libXv:

• CVE-2016-5407: insufficient validation of data from the X server can cause out of boundary memory and memory corruption (bsc#1003017)

libXvMC:

• CVE-2016-7953: insufficient validation of data from the X server can cause a one byte buffer read underrun (bsc#1003023)

libXrender:

• CVE-2016-7949, CVE-2016-7950: insufficient validation of data from the X server can cause out of boundary memory writes (bsc#1003002)

libXrandr:

• CVE-2016-7947, CVE-2016-7948: insufficient validation of data from the X server can cause out of boundary memory writes (bsc#1003000)

This update for the X Window System client libraries fixes a class of privilege escalation issues.

A malicious X Server could send specially crafted data to X clients, which allowed for triggering crashes, or privilege escalation if this relationship was untrusted or crossed user or permission level boundaries.

libX11, libXfixes, libXi, libXrandr, libXrender, libXtst, libXv, libXvMC were fixed, specifically:

libX11:

• CVE-2016-7942: insufficient validation of data from the X server allowed out of boundary memory read (bsc#1002991)

libXfixes:

• CVE-2016-7944: insufficient validation of data from the X server can cause an integer overflow on 32 bit architectures (bsc#1002995)

libXi:

• CVE-2016-7945, CVE-2016-7946: insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service) (bsc#1002998)

libXtst:

• CVE-2016-7951, CVE-2016-7952: insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service) (bsc#1003012)

libXv:

• CVE-2016-5407: insufficient validation of data from the X server can cause out of boundary memory and memory corruption (bsc#1003017)

libXvMC:

• CVE-2016-7953: insufficient validation of data from the X server can cause a one byte buffer read underrun (bsc#1003023)

libXrender:

• CVE-2016-7949, CVE-2016-7950: insufficient validation of data from the X server can cause out of boundary memory writes (bsc#1003002)

libXrandr:

• CVE-2016-7947, CVE-2016-7948: insufficient validation of data from the X server can cause out of boundary memory writes (bsc#1003000)

This update for xorg-x11-libs fixes the following issues:

• insufficient validation of data from the X server can cause a one byte buffer read underrun (bsc#1003023, CVE-2016-7953)
• insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service) (bsc#1003012, CVE-2016-7951, CVE-2016-7952)
• insufficient validation of data from the X server can cause out of boundary memory writes (bsc#1003000, CVE-2016-7947, CVE-2016-7948)
• insufficient validation of data from the X server can cause out of boundary memory access or endless loops (Denial of Service). (bsc#1002998, CVE-2016-7945, CVE-2016-7946)

It was discovered that libXtst did not properly handle certain RECORD replies from the X server. A malicious X server could possibly use this issue to cause libXtst clients to crash, resulting in a denial of service. (CVE-2026-94286)

Tobias Stoeckmann discovered that libXtst did not properly handle certain memory operations. A malicious X server could possibly use this issue to cause libXtst to access memory out of bounds, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS. (CVE-2016-7951)

Tobias Stoeckmann discovered that libXtst did not properly handle certain replies from the X server. A malicious X server could possibly use this issue to cause libXtst to enter an infinite loop, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS. (CVE-2016-7952)