Every CVE Search/ Get API key

CVE-2026-71393

Heap Buffer Overflow in GNU Emacs for Android

5.3 Medium

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
Passive

What an attacker can affect

Confidentiality
None
Integrity
None
Availability
Low

Exploit likelihood

0.67%Up 0.3 points since Aug 11, 2026
90%50%10%1%

What each source reports

CVE List Score used 5.3

Heap Buffer Overflow in GNU Emacs for Android

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
CVE-2026-71393
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N
Weakness
CWE-190
Updated
2026-11-02
EUVDEUVD-2026-55258 5.3

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
EUVD-2026-55258
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N
Updated
2026-11-02
GitHub AdvisoriesGHSA-4rgf-7285-chf8 5.3

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt...

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
GHSA-4rgf-7285-chf8
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness
CWE-190
Updated
2026-11-02
NVD 5.3

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
CVE-2026-71393
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness
CWE-190
Updated
2026-11-02
OSV 5.3

Heap Buffer Overflow in GNU Emacs for Android

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
CVE-2026-71393
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N
Weakness
CWE-190
Updated
2026-11-02
OSVDEBIAN-CVE-2026-71393 5.3

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution. This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
DEBIAN-CVE-2026-71393
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Updated
2026-11-02
OSVUBUNTU-CVE-2026-71393 5.3

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution. This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Record
UBUNTU-CVE-2026-71393
CVSS 4.0
5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
emacs24
Ubuntu:Pro:16.04:LTS
All versions, plus listed versions
24.5+1-1ubuntu224.5+1-1ubuntu424.5+1-1ubuntu524.5+1-1ubuntu624.5+1-1ubuntu7
Show 6 moreShow less
24.5+1-6ubuntu124.5+1-6ubuntu1.124.5+1-6ubuntu1.1+esm124.5+1-6ubuntu1.1+esm224.5+1-6ubuntu1.1+esm324.5+1-6ubuntu1.1+esm4
None known
xemacs21
Ubuntu:16.04:LTS
All versions, plus listed versions
21.4.22-4ubuntu321.4.22-14ubuntu1
None known
xemacs21-packages
Ubuntu:16.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.2-2
None known
emacs25
Ubuntu:Pro:18.04:LTS
All versions, plus listed versions
25.2+1-625.2+1-6ubuntu0.1~esm2
None known
xemacs21
Ubuntu:18.04:LTS
All versions, plus listed versions
21.4.24-4ubuntu121.4.24-5ubuntu1
None known
xemacs21-packages
Ubuntu:18.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.2-4
None known
emacs
Ubuntu:Pro:20.04:LTS
All versions, plus listed versions
1:26.3+1-1ubuntu11:26.3+1-1ubuntu21:26.3+1-1ubuntu2+esm11:26.3+1-1ubuntu2+esm2
None known
xemacs21
Ubuntu:20.04:LTS
All versions, plus listed versions
21.4.24-8build121.4.24-9
None known
xemacs21-packages
Ubuntu:20.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.2-42009.02.17.dfsg.2-5
None known
xemacs21
Ubuntu:22.04:LTS
All versions, plus listed versions
21.4.24-9ubuntu2
None known
Show 11 moreShow less
Affected packages
PackageAffectedFixed
xemacs21-packages
Ubuntu:22.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.2-5
None known
emacs
Ubuntu:Pro:22.04:LTS
All versions, plus listed versions
1:27.1+1-3ubuntu31:27.1+1-3ubuntu51:27.1+1-3ubuntu5.11:27.1+1-3ubuntu5.21:27.1+1-3ubuntu5.2+esm1
None known
xemacs21
Ubuntu:24.04:LTS
All versions, plus listed versions
21.4.24-1221.4.24-12build221.4.24-12build3
None known
xemacs21-packages
Ubuntu:24.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.3-22009.02.17.dfsg.3-3
None known
emacs
Ubuntu:Pro:24.04:LTS
All versions, plus listed versions
1:29.1+1-5ubuntu11:29.2+1-1ubuntu11:29.2+1-2ubuntu41:29.3+1-1ubuntu21:29.3+1-1ubuntu2+esm11:29.3+1-1ubuntu2+esm31:29.3+1-1ubuntu2+esm4
None known
emacs
Ubuntu:26.10
All versions, plus listed versions
1:30.2+1-2ubuntu11:30.2+1-6ubuntu11:30.2+1-11ubuntu1
None known
xemacs21
Ubuntu:26.10
All versions, plus listed versions
21.4.24-12build3
None known
xemacs21-packages
Ubuntu:26.10
All versions, plus listed versions
2009.02.17.dfsg.3-3build1
None known
xemacs21
Ubuntu:26.04:LTS
All versions, plus listed versions
21.4.24-12build3
None known
xemacs21-packages
Ubuntu:26.04:LTS
All versions, plus listed versions
2009.02.17.dfsg.3-32009.02.17.dfsg.3-3build1
None known
emacs
Ubuntu:Pro:26.04:LTS
All versions, plus listed versions
1:30.1+1-9ubuntu11:30.2+1-1ubuntu21:30.2+1-2ubuntu11:30.2+1-2ubuntu1+esm1
None known

History

History
RecordedChangedSources
affected
first indexedCVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-71393 is a medium vulnerability (CVSS 5.3) in Gnu Emacs, published August 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.67%, the 52nd percentile. No source names a fixed version.

References

Show 4 moreShow less
MoveEnter Open