CVE-2021-21572

EUVD-2021-8844 · Published Jun 24, 2021

Dell BIOSConnect feature contains a buffer overflow vulnerability. An authenticated malicious admin user with local access to the system may potentially exploit this vulnerability to run arbitrary code and bypass UEFI restrictions.

Technologies

Dell Vostro 3500 FirmwareDell Xps 13 9310 FirmwareDell Xps 13 9310Dell Optiplex 7080Dell Optiplex 7490 All-In-One FirmwareDell Vostro 5502Dell Latitude 3520 FirmwareDell Latitude 7310Dell Latitude 5410Dell Inspiron 5409Dell Inspiron 7500 2-In-1 FirmwareDell Inspiron 7506Dell Vostro 5301 FirmwareDell Latitude 9520 FirmwareDell Latitude 5511Dell Latitude 7520 FirmwareDell Inspiron 7700 Aio FirmwareDell Latitude 5521Dell Precision 3550 FirmwareDell Latitude 7310 FirmwareDell Vostro 3881 FirmwareDell Xps 13 2In1 9310Dell Latitude 9510 FirmwareDell Xps 13 2In1 9310 FirmwareDell Vostro 5890Dell Latitude 5511 FirmwareDell Precision 3440 FirmwareDell Optiplex 7780 All-In-One FirmwareDell Inspiron 7500 FirmwareDell Inspiron 7400 FirmwareDell Latitude 5320 2-In-1 FirmwareDell Vostro 5310 FirmwareDell Vostro 15 5510Dell Inspiron 7706 2-In-1Dell Latitude 7320 Detachable FirmwareDell Optiplex 3280 All-In-OneDell Optiplex 7090 TowerDell Inspiron 5402Dell Inspiron 5400 Aio FirmwareDell Vostro 5300Dell Latitude 3420 FirmwareDell Vostro 3501 FirmwareDell Inspiron 5300Dell Precision 3640 FirmwareDell Inspiron 5409 FirmwareDell Inspiron 7300 FirmwareDell G7 7500 FirmwareDell Inspiron 5401Dell Latitude 3510 FirmwareDell Latitude 5520 FirmwareDell Optiplex 5490 Aio FirmwareDell Latitude 5310 FirmwareDell Precision 3551Dell G15 5511Dell Precision 3650 MtDell Optiplex 5090 TowerDell Vostro 14 5410Dell Vostro 3400Dell Inspiron 5408Dell Xps 17 9710Dell Precision 7550 FirmwareDell Precision 7760Dell Latitude 7520Dell Inspiron 5401 AioDell Precision 3640Dell Precision 17 M5750Dell Inspiron 7700 AioDell Inspiron 7400Dell Inspiron 5509Dell Latitude 7410 FirmwareDell Optiplex 5080Dell Inspiron 5400 2-In-1 FirmwareDell Precision 3550Dell Precision 5550 FirmwareDell Latitude 9420Dell Optiplex 7780 All-In-OneDell Latitude 3120Dell Vostro 3890Dell Xps 15 9500 FirmwareDell G5 5500Dell Xps 15 9510 FirmwareDell Latitude 5310 2-In-1 FirmwareDell G5 5500 FirmwareDell Optiplex 5090 Tower FirmwareDell Vostro 3681Dell Inspiron 5502Dell Precision 7550Dell Optiplex 3090 UffDell Xps 13 9305 FirmwareDell Chengming 3991 FirmwareDell Latitude 3120 FirmwareDell Latitude 7320 FirmwareDell G7 7700Dell Vostro 3500Dell Latitude 5520Dell Latitude 5320Dell Vostro 3681 FirmwareDell Latitude 5320 FirmwareDell Vostro 5402 FirmwareDell Inspiron 5400 AioDell Latitude 7320Dell Precision 3650 Mt FirmwareDell Vostro 15 5510 FirmwareDell Precision 5560Dell Precision 3561 FirmwareDell Inspiron 5406 2N1 FirmwareDell Inspiron 7501Dell Precision 3560 FirmwareDell Latitude 5410 FirmwareDell Vostro 7500 FirmwareDell Precision 3561Dell Latitude 3510Dell Precision 5760 FirmwareDell Inspiron 14 5418Dell Inspiron 7506 FirmwareDell Inspiron 5310 FirmwareDell Latitude 3320 FirmwareDell Optiplex 7490 All-In-OneDell Vostro 3888 FirmwareDell Optiplex 7090 UffDell Vostro 3690Dell Latitude 5521 FirmwareDell Latitude 9520Dell Optiplex 3280 All-In-One FirmwareDell Optiplex 7090 Uff FirmwareDell Latitude 5411Dell Vostro 3888Dell Vostro 5402Dell Inspiron 5410 2-In-1 FirmwareDell Inspiron 7500Dell Inspiron 15 7510Dell Inspiron 5410 2-In-1Dell Inspiron 7706 2-In-1 FirmwareDell Inspiron 5301 FirmwareDell G15 5510Dell Inspiron 5301Dell G15 5511 FirmwareDell Inspiron 7300Dell Inspiron 3880 FirmwareDell Optiplex 7090 Tower FirmwareDell Precision 5560 FirmwareDell Precision 5760Dell G3 3500Dell Vostro 5401Dell Inspiron 3891Dell Vostro 5501Dell Vostro 5880Dell Precision 3440Dell Inspiron 15 5518Dell Latitude 9510Dell Inspiron 3501Dell Inspiron 3880Dell Optiplex 3080Dell Inspiron 7306 2-In-1 FirmwareDell Inspiron 7501 FirmwareDell Inspiron 15 7510 FirmwareDell Latitude 3410Dell Latitude 5411 FirmwareDell Latitude 5510 FirmwareDell G15 5510 FirmwareDell Inspiron 5408 FirmwareDell Precision 3560Dell Vostro 7500Dell Inspiron 5401 FirmwareDell Xps 15 9510Dell Latitude 5420 FirmwareDell Optiplex 7480 All-In-OneDell Xps 17 9710 FirmwareDell Inspiron 3891 FirmwareDell Vostro 5300 FirmwareDell Inspiron 5400 2-In-1Dell Latitude 7410Dell Latitude 9410Dell Precision 5550Dell Inspiron 5401 Aio FirmwareDell Latitude 5510Dell Inspiron 5509 FirmwareDell Vostro 5401 FirmwareDell Inspiron 5310Dell Inspiron 15 5518 FirmwareDell Precision 7750 FirmwareDell Optiplex 7080 FirmwareDell Latitude 5421 FirmwareDell Vostro 5310Dell Chengming 3991Dell Inspiron 5406 2N1Dell Inspiron 5508Dell Latitude 7210 2-In-1 FirmwareDell Vostro 5501 FirmwareDell G3 3500 FirmwareDell Optiplex 7480 All-In-One FirmwareDell Xps 13 9305Dell Latitude 9420 FirmwareDell Inspiron 5501Dell Chengming 3990Dell Inspiron 5300 FirmwareDell Optiplex 5490 AioDell Vostro 3501Dell Inspiron 3881Dell Optiplex 3090 Uff FirmwareDell Inspiron 7500 2-In-1Dell Chengming 3990 FirmwareDell Precision 7750Dell Vostro 3690 FirmwareDell Latitude 7320 DetachableDell Inspiron 7610Dell Vostro 3890 FirmwareDell Inspiron 3881 FirmwareDell Inspiron 7300 2-In-1Dell Precision 3450 FirmwareDell Latitude 5421Dell Xps 15 9500Dell Inspiron 5402 FirmwareDell Alienware M15 R6Dell Inspiron 5508 FirmwareDell Latitude 5320 2-In-1Dell Vostro 5502 FirmwareDell Precision 17 M5750 FirmwareDell Vostro 14 5410 FirmwareDell Inspiron 14 5418 FirmwareDell Inspiron 3501 FirmwareDell Vostro 3881Dell Latitude 3410 FirmwareDell Inspiron 7610 FirmwareDell Latitude 7210 2-In-1Dell Vostro 15 7510 FirmwareDell Inspiron 5501 FirmwareDell Vostro 15 7510Dell Latitude 9410 FirmwareDell Inspiron 7306 2-In-1Dell Vostro 5301Dell Latitude 3320Dell Precision 7560Dell Optiplex 5080 FirmwareDell Precision 3450Dell Vostro 5880 FirmwareDell G7 7500Dell Latitude 5310 2-In-1Dell Optiplex 3080 FirmwareDell Latitude 3520Dell Precision 7760 FirmwareDell Vostro 3400 FirmwareDell Vostro 5890 FirmwareDell Precision 7560 FirmwareDell Inspiron 7300 2-In-1 FirmwareDell Xps 17 9700Dell Inspiron 5502 FirmwareDell Latitude 7420 FirmwareDell Precision 3551 FirmwareDell Latitude 3420Dell Latitude 5310Dell Alienware M15 R6 FirmwareDell Xps 17 9700 FirmwareDell Latitude 5420Dell Latitude 7420Dell G7 7700 Firmware

Weaknesses

CWE-122CWE-787

CVSS scores

v3.17.5CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
v2.06.9AV:L/AC:M/Au:N/C:C/I:C/A:C

MITRE ATT&CK

Inferred

Where this vulnerability fits in an attack

ReconImpact

Privilege Escalation

T1068Exploitation for Privilege Escalation

References

https://www.dell.com/support/kbdoc/en-us/000188682

Potentially impacted assets

See if this affects your attack surface

Latest trending attack

Criticalyesterday

Google Brotli decoder - Remote Code Execution via compressed requests (Exploitation Check)

This control is the second step of the Patrowl response to CVE-2026-111497 (Node2Shell). It complements the first control of 22 October 2026, which focused on the Node.js runtime, and does not replace it. Why a second control CVE-2026-111497 is an out-of-bounds write in the Google Brotli decoder, the library that decompresses Brotli ("br") data. It was first published as a Node.js vulnerability, because Node.js bundles this decoder. Later publications showed that the flaw is in the library itself. Every product that embeds an affected version of the decoder is concerned, whatever its language or vendor. A public proof of concept demonstrates code execution. Any server that decompresses request bodies sent with "Content-Encoding: br" exposes the decoder to unauthenticated attackers. Known cases include Express 5 and NestJS 11 on Node.js, Koa and Fastify setups, Bun, Envoy and Istio with request decompression enabled, and any application or reverse proxy that decodes Brotli request bodies with an affected library. The flaw also works in the other direction. A malicious server can compromise an unpatched client that decodes a Brotli response, for example Node.js fetch(), Python clients (requests, httpx, aiohttp, Scrapy) with the Brotli or brotlicffi package, or libcurl builds with Brotli support. What this control checks Patrowl sends small, valid Brotli-compressed requests to each asset and observes whether the server decodes them. The check does not depend on the technology: it detects the behaviour, whatever the stack behind it. These requests are what any legitimate client could send. They never reach the vulnerable code path and cannot affect the availability of the service. How to read the result Potentially impacted means the asset decodes Brotli request bodies: the attack surface is exposed. It does not confirm that the asset is vulnerable. The version of the Brotli decoder in use is not visible from the outside. This check covers applications that parse request bodies on their root path. A Not impacted result does not rule out exposure on other routes, nor on the client side. Checking the versions on the servers remains the only exhaustive verification. Two situations are possible. When the decoding is done by your own application or reverse proxy, identify the component and update it. If an update is not possible right away, reject requests with "Content-Encoding: br" at the reverse proxy or WAF. When the asset is hosted on a managed platform or behind a CDN (for example Platform.sh, Upsun or Fastly), the decoding may be done by the provider's edge router, in front of your application. You cannot patch it yourself, but this router handles all the traffic of your site. Ask your provider to confirm that its edge components are patched against CVE-2026-111497. Assets hosted on a managed platform or behind a CDN carry the tag "paas: platform.sh" or "cdn: fastly" in the asset view: for these assets, the Brotli decoding is done by the provider's edge router, in front of your application, and only the provider can patch it. Affected and fixed versions Google Brotli 1.0.3 to 1.2.0 are affected, fixed in 1.0.10, 1.1.1 and 1.2.1. Fixed releases of the main products embedding it: Node.js 22.23.4, 24.22.1 and 26.12.1 (end-of-life lines 20.x and older and 25.x receive no fix), Bun 1.4.4, Envoy 1.37.8, 1.38.6, 1.39.3 and 1.40.0, Istio 1.29.9, 1.30.6 and 1.31.2, Python Brotli 1.2.1 and brotlicffi 1.2.1.0. Products that link against the system library depend on the Brotli package of the Linux distribution. Recommendations Update every component that embeds the Brotli decoder (only real fix). Start with the assets flagged by this control. Restart the processes after the update. Rebuild containers, single-executable applications and appliances that bundle an affected runtime or library. Reduce the exposure until the update is deployed. Reject requests with "Content-Encoding: br" at the reverse proxy, load balancer or WAF, case-insensitively and including lists such as "gzip, br". On Envoy and Istio, disable request decompression for Brotli. Contact your edge provider about the status of the pathing (Fastly / Plateform.sh) Review outbound calls. List the features that fetch content from servers you do not control, and patch the services that host them first.

CVE-2021-21572

Technologies

Weaknesses

CVSS scores

MITRE ATT&CK

References

Potentially impacted assets

Latest trending attack

Google Brotli decoder - Remote Code Execution via compressed requests (Exploitation Check)

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