Malicious PDF — malware analysis report

Static analysis result for SHA-256 26866244e1743f4d…

MALICIOUS

PDF

12.2 KB
MD5: a85dac42aac15a4fdcae52f5a71a2a36 SHA-1: fe731311e95149b392d8fdf500470957b918d7fb SHA-256: 26866244e1743f4de4fe035098a6d4909ced75894dcf2f71b577ab8e7475a364
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF document contains embedded JavaScript, specifically leveraging the 'Collab.collectEmailInfo' method to exploit CVE-2007-5659. This technique is used to decode and execute a hex-encoded JavaScript stager. The stager is responsible for downloading and executing a second-stage payload, indicated by the presence of multiple deobfuscated JavaScript files and ClamAV detection as 'Pdf.Exploit.Agent-36063'. The primary attack vector is the exploitation of a known PDF vulnerability.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
3e44b0c3ea6f69d5860247c5266d7ea593125881680afb6093624d5d6b7fa0c8
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5173 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
47e76264e106c19ce6e1eaa650cc63847671b17ee3a49e70d4fb26295c5297f6
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12314 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
6ad74bd39b05f800371084e8c3d4cb8c8a9e60956f7016f20766e8278e29a109
deobfuscated-js PDF JavaScript deobfuscation pass 77360 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).