Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
7 results
Jul 1, 2026FatFs R0.16 and earlier contains a downstream-caller vulnerability pattern associated with FatFs long filename handling.CVE-2026-6688 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914High 7.6
FatFs R0.16 and earlier contains a downstream-caller vulnerability pattern associated with FatFs long filename handling. With LFN enabled, fno.fname can be up to 255 characters; many callers copy it into short fixed buffers without bounds checks, causing overflow. This maps to CWE-120 (Buffer Copy without Checking Size of Input). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (7.6, High). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Jul 1, 2026FatFs R0.16 and earlier contains a stack overflow bug in f_getlabel() because exFAT label length (XDIR_NumLabel) is trusted without enforcing spec maximums.CVE-2026-6687 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914High 7.6
FatFs R0.16 and earlier contains a stack overflow bug in f_getlabel() because exFAT label length (XDIR_NumLabel) is trusted without enforcing spec maximums. This maps to CWE-121 (Stack-based Buffer Overflow). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (7.6, High). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Jul 1, 2026FatFs R0.16 and earlier contains an uninitialized cluster exposure when f_lseek() extends files beyond EOF without zero-filling newly allocated clusters.CVE-2026-6686 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914Medium 4.6
FatFs R0.16 and earlier contains an uninitialized cluster exposure when f_lseek() extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 (Use of Uninitialized Resource). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Jul 1, 2026FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enablinCVE-2026-6684 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914Medium 4.6
FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Jul 1, 2026FatFs R0.16 and earlier contains a divide-by-zero in exFAT sync logic bug when crafted metadata causes n_fatent - 2 to be zero during write/sync operations.CVE-2026-6683 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914Medium 4.6
FatFs R0.16 and earlier contains a divide-by-zero in exFAT sync logic bug when crafted metadata causes n_fatent - 2 to be zero during write/sync operations. This maps to CWE-369 (Divide By Zero). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). Network-delivered update media can make this remote in some pipelines. The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Jul 1, 2026In FatFS R0.16 and earlier contains a FAT32 integer overflow bug in mount_volume() where fasize *= fs->n_fats can wrap, leading to attacker-controlled file-sizeCVE-2026-6682 · Other software · ChaN · reported by 44488dab-36db-4358-99f9-bc116477f914High 7.6
In FatFS R0.16 and earlier contains a FAT32 integer overflow bug in mount_volume() where fasize *= fs->n_fats can wrap, leading to attacker-controlled file-size metadata and unsafe read lengths in downstream callers. This maps to CWE-190 (Integer Overflow or Wraparound). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (7.6, High). Remote delivery is also possible in OTA/update pipelines. The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.
- Product
- FatFs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordelm-chan.orggithub.com
Mar 27, 2017Heap-based buffer overflow in the verify_vbr_checksum function in exfatfsck in exfat-utils before 1.2.1 allows remote attackers to cause a denial of service (inCVE-2015-8026 · Other software · Exfat Project · reported by MITREHigh 7.8
Heap-based buffer overflow in the verify_vbr_checksum function in exfatfsck in exfat-utils before 1.2.1 allows remote attackers to cause a denial of service (infinite loop) or possibly execute arbitrary code via a crafted filesystem.
- Product
- Exfat
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordopenwall.comsecurityfocus.com
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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