CVE-2021-3695
published 2022-07-06CVE-2021-3695: A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption…
PriorityP425medium4.5CVSS 3.1
AVLACHPRLUINSUCLILAL
EPSS
0.46%
37.2th percentile
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
Affected
46 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | grub2 | < grub2 2.06-3 (bookworm) | grub2 2.06-3 (bookworm) |
| fedoraproject | fedora | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | >= 0 < 2.06-3~deb11u1 | 2.06-3~deb11u1 |
| gnu | grub2 | >= 0 < 2.06-3 | 2.06-3 |
| gnu | grub2 | >= 0 < 2.06-3 | 2.06-3 |
| gnu | grub2 | >= 0 < 2.06-3 | 2.06-3 |
| gnu | grub2 | >= 2.00 < 2.12 | 2.12 |
| msrc | azl3_grub2_2.06-14_on_azure_linux_3.0 | — | — |
| msrc | azl3_grub2_2.06-23_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| redhat | developer_tools | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux_eus | — | — |
| redhat | enterprise_linux_eus | — | — |
| redhat | enterprise_linux_eus | — | — |
| redhat | enterprise_linux_eus | — | — |
| redhat | enterprise_linux_for_power_little_endian | — | — |
| redhat | enterprise_linux_for_power_little_endian | — | — |
CVSS provenance
nvdv3.14.5MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
nvdv2.04.4MEDIUMAV:L/AC:M/Au:N/C:P/I:P/A:P
osv4.5MEDIUM
vendor_debian4.5MEDIUM
vendor_msrc4.5MEDIUM
vendor_redhat4.5MEDIUM
vendor_ubuntu4.5MEDIUM
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OSV
grub2-signed, grub2-unsigned, shim, and shim-signed vulnerability
osv·2023-09-08·CVSS 4.5
CVE-2021-3695 [MEDIUM] grub2-signed, grub2-unsigned, shim, and shim-signed vulnerability
grub2-signed, grub2-unsigned, shim, and shim-signed vulnerability
Daniel Axtens discovered that specially crafted images could cause a
heap-based out-of-bonds write. A local attacker could possibly use
this to circumvent secure boot protections. (CVE-2021-3695)
Daniel Axtens discovered that specially crafted images could cause
out-of-bonds read and write. A local attacker could possibly use this
to circumvent secure boot protections. (CVE-2021-3696)
Daniel Axtens discovered that specially crafted images could cause
buffer underwrite which allows arbitrary data to be written to a heap.
A local attacker could possibly use this to circumvent secure
boot protections. (CVE-2021-3697)
It was discovered that GRUB2 configuration files were created with
the wrong permissions. An attacker could
GHSA
GHSA-xjhh-w3rj-8mxm: A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area
ghsa_unreviewed·2022-07-07
CVE-2021-3695 [MEDIUM] CWE-787 GHSA-xjhh-w3rj-8mxm: A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
OSV
CVE-2021-3695: A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area
osv·2022-07-06·CVSS 4.5
CVE-2021-3695 [MEDIUM] CVE-2021-3695: A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
Ubuntu
GRUB2 vulnerabilities
vendor_ubuntu·2023-09-08·CVSS 4.5
CVE-2022-28737 [MEDIUM] GRUB2 vulnerabilities
Title: GRUB2 vulnerabilities
Summary: Several security issues were fixed in GRUB2.
Daniel Axtens discovered that specially crafted images could cause a
heap-based out-of-bonds write. A local attacker could possibly use
this to circumvent secure boot protections. (CVE-2021-3695)
Daniel Axtens discovered that specially crafted images could cause
out-of-bonds read and write. A local attacker could possibly use this
to circumvent secure boot protections. (CVE-2021-3696)
Daniel Axtens discovered that specially crafted images could cause
buffer underwrite which allows arbitrary data to be written to a heap.
A local attacker could possibly use this to circumvent secure
boot protections. (CVE-2021-3697)
It was discovered that GRUB2 configuration files were created with
the wrong permissions.
Microsoft
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and
vendor_msrc·2022-07-12·CVSS 4.5
CVE-2021-3695 [MEDIUM] CWE-787 A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to
Red Hat
grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap
vendor_redhat·2022-06-07·CVSS 4.5
CVE-2021-3695 [MEDIUM] CWE-787 grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap
grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
A flaw was found in grub 2, where a crafted 16-bit grayscale PNG image may lead to an out-of-bounds write. This flaw allows an attacker to corrupt the data on the heap port
Debian
CVE-2021-3695: grub2 - A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the he...
vendor_debian·2021·CVSS 4.5
CVE-2021-3695 [MEDIUM] CVE-2021-3695: grub2 - A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the he...
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
Scope: local
bookworm: resolved (fixed in 2.06-3)
bullseye: resolved (fixed in 2.06-3~deb11u1)
forky: resolved (fixed in 2.06-3)
sid: resolved (fixed in 2.06-3)
trixie: resolved (fixed in 2.06-3)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2022-07-06
Published