{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74733", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.930Z", "datePublished": "2026-08-22T15:33:21.579Z", "dateUpdated": "2026-10-30T12:30:25.982Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:30:25.982Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ngpio: pca953x: fix pca953x_irq_bus_sync_unlock regmap lock\n\nLocking is disabled in the regmap config as this driver uses its own\nlock. This means that all calls to regmap functions (read or write) must\nhold the i2c_lock. The function pca953x_irq_bus_sync_unlock() did not do\nthis, and it was therefore possible that multiple threads could cause an\nincorrect register to be read/written.\n\nA previous patch partly fixed this, but only protected the write to the\ninterrupt mask register, and not the read from the direction register."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable pca953x_irq_bus_sync_unlock() path is reached only through local kernel interfaces\u2014GPIO chardev ioctls (GPIO_V2_GET_LINE_IOCTL, GPIO_V2_LINE_SET_CONFIG_IOCTL, GPIO_V2_LINE_SET_VALUES_IOCTL), legacy sysfs GPIO, or concurrent in-kernel GPIO/IRQ ops\u2014not via any network or physical bus-facing attack surface.\nAC:L - An attacker drives both racing sides directly: one thread loops IRQ edge-detection setup/teardown (request_irq \u2192 irq_bus_sync_unlock) while another hammers GPIO value/direction writes holding i2c_lock; the original report reproduced the race ~1 in 1000 boots, so deliberate concurrency wins reliably.\nPR:L - Exploitation requires an open file descriptor on /dev/gpiochipN or sysfs GPIO access; on embedded, industrial, medical, and automotive boards using pca953x expanders, udev routinely grants gpio group membership to unprivileged local users.\nUI:N - No victim interaction is required\u2014the attacker performs all GPIO ioctl and IRQ configuration steps in its own threads without needing another user to mount, open, or configure devices.\nS:U - Corruption is confined to the kernel and the same on-board I2C GPIO expander; it does not cross VM, container, IOMMU, or other security-boundary scopes into a different authority.\nC:H - With regmap disable_locking=true, the unprotected pca953x_read_regs() direction read races locked regmap paths, corrupting the maple regcache and returning data from the wrong register\u2014yielding kernel heap UAF read and unintended register-state disclosure.\nI:H - Racing regmap transactions write interrupt-latch/direction data into wrong expander registers (documented output-register corruption), arbitrarily toggling safety-critical GPIO outputs; concurrent unsynchronized regcache writes provide a heap corruption/write primitive.\nA:H - Concurrent regcache maple-tree corruption from unsynchronized regmap access can trigger kernel oops/panic via double-free; miswritten interrupt masks or direction registers can wedge expander IRQ handling and GPIO consumers in a persistent denial-of-service."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/gpio/gpio-pca953x.c"], "versions": [{"version": "58a5c93bd1a6e949267400080f07e57ffe05ec34", "lessThan": "58ed56c093a857c19f04cf3db1f02d2e793aec88", "status": "affected", "versionType": "git"}, {"version": "e2ecdddca80dd845df42376e4b0197fe97018ba2", "lessThan": "5d05c4252c09ce10624be2197853c80bf87424e4", "status": "affected", "versionType": "git"}, {"version": "bfc6444b57dc7186b6acc964705d7516cbaf3904", "lessThan": "41255e64eb9dd87b0b8675f4e47a9c67bcef6e39", "status": "affected", "versionType": "git"}, {"version": "bfc6444b57dc7186b6acc964705d7516cbaf3904", "lessThan": "bf3f37c2d40b51deb79aea910f28999d7c8c6b5a", "status": "affected", "versionType": "git"}, {"version": "bfc6444b57dc7186b6acc964705d7516cbaf3904", "lessThan": "e6a2f5f845f50b0c4299bace5111f56d3390a090", "status": "affected", "versionType": "git"}, {"version": "bfc6444b57dc7186b6acc964705d7516cbaf3904", "lessThan": "9dc325327babe7f159e84cbe9380a45342da0585", "status": "affected", "versionType": "git"}, {"version": "de7cffa53149c7b48bd1bb29b02390c9f05b7f41", "status": "affected", "versionType": "git"}, {"version": "6.1.101", "lessThan": "6.1.191", "status": "affected", "versionType": "semver"}, {"version": "6.6.42", "lessThan": "6.6.160", "status": "affected", "versionType": "semver"}, {"version": "6.9.11", "lessThan": "6.10", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/gpio/gpio-pca953x.c"], "versions": [{"version": "6.10", "status": "affected"}, {"version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.9", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.101", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.42", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.1.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9.11"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/58ed56c093a857c19f04cf3db1f02d2e793aec88"}, {"url": "https://git.kernel.org/stable/c/5d05c4252c09ce10624be2197853c80bf87424e4"}, {"url": "https://git.kernel.org/stable/c/41255e64eb9dd87b0b8675f4e47a9c67bcef6e39"}, {"url": "https://git.kernel.org/stable/c/bf3f37c2d40b51deb79aea910f28999d7c8c6b5a"}, {"url": "https://git.kernel.org/stable/c/e6a2f5f845f50b0c4299bace5111f56d3390a090"}, {"url": "https://git.kernel.org/stable/c/9dc325327babe7f159e84cbe9380a45342da0585"}], "title": "gpio: pca953x: fix pca953x_irq_bus_sync_unlock regmap lock", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-74733", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T19:15:53.820928Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:16:12.549Z"}}]}}