ESF-IDF: Heap buffer overflow in protocomm Security2 over Bluetooth
ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a heap buffer overflow exists in the Security Scheme 2 (SRP6a) session-setup path of the protocomm component. The first-phase handler (handle_session_command0() in components/protocomm/src/security/security2.c) trusts the length of a client-supplied protobuf field for the SRP6a username and copies it into a buffer whose size is derived from a narrower destination type. The resulting truncation-versus-copy asymmetry corrupts the heap when an oversized value is supplied. This issue has been patched in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for help- Published
- Jun 9, 2026
- Updated
- Jul 23, 2026
- EPSS
- 0.5% · 42th percentile
- CWE
- CWE-122
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
28
Monitor
Low priority for now.
- CVSS
- 28 / 40 · 7.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · GitHub_M
- 7.1
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| espressif | esp-idf | cpe:2.3:a:espressif:esp-idf |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- espressif esp-idf5.2.6
- espressif esp-idf5.3.5
- espressif esp-idf5.4.4
- espressif esp-idf5.5.4
- espressif esp-idf6.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
espressif esp-idf
- = 5.2.6, = 5.3.5, = 5.4.4, = 5.5.4, = 6.0affected
Same product
espressif: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-45328ESF-IDF: Out-of-Bounds Write in ESP-TEE Secure Service Wrappers35Monitor
- CVE-2024-53406Espressif Esp idf v5.3.0 is vulnerable to Insecure Permissions resulting in Authentication bypass.35Monitor
- CVE-2022-24893Espressif Bluetooth Mesh Stack Vulnerable to Out-of-bounds Write leading to memory buffer corruption35Monitor
- CVE-2021-28139The Bluetooth Classic implementation in Espressif ESP-IDF 4.4 and earlier does not properly restrict the Feature Page upon reception of an L35Monitor
- CVE-2026-25532ESF-IDF is Vulnerable to WPS Enrollee Fragment Integer Underflow32Monitor
- CVE-2024-33453Buffer Overflow vulnerability in esp-idf v.5.1 allows a remote attacker to obtain sensitive information via the externalId component.32Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone on the same network segment can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- low · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Adjacent
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- Low
- Availability impact
- High
Weakness class (CWE)
CWE-122 · Heap-based Buffer OverflowCVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- github.com/espressif/esp-idf/commit/0ea58d79845ad674d0358d5de246015a68c4cb4f
- github.com/espressif/esp-idf/commit/56c3e385611e63162d0f2f8504ac4ae2ccfccef0
- github.com/espressif/esp-idf/commit/71eb2dbe6aaef830719ecac8edf409e2992b64b2
- github.com/espressif/esp-idf/commit/9b4cacf9cbc69379972de6a2247fcf5af9240961
- github.com/espressif/esp-idf/commit/a2f4554f10ba075c98cbc67464db096ba32497cf
- github.com/espressif/esp-idf/commit/f5d24a7e919bc5f447091479656b86da6762a103
- github.com/espressif/esp-idf/security/advisories/GHSA-9r76-858f-v6jh
Vendor advisories and official records. Exploit/PoC links are deliberately left out.