Malicious PDF — malware analysis report

Static analysis result for SHA-256 af693f4a725b9cbf…

MALICIOUS

PDF

11.9 KB
MD5: b46c85ee76fbbabcf0064f23f0a320f7 SHA-1: 71a2be8559c1597fba96b5f50366fa3cbd5c94ab SHA-256: af693f4a725b9cbf9993e8ec6cd509abb86895f09072fb2adb260d3369b725be
186 Risk Score

Malware Insights

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

The critical heuristic CVE_2007_5659 indicates the exploitation of a known PDF vulnerability (Collab.collectEmailInfo) to execute a JavaScript stager. This stager is heavily obfuscated but ultimately aims to download and execute a secondary payload. The presence of multiple deobfuscated JavaScript files further supports this attack vector. The ClamAV detection also confirms the malicious nature of the file.

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
f4a7225bd7fd2aa0a626650cb7289fade042be1d8bbc64161b8d83c4600a760c
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5067 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
9b4ea490a100ed763b5ea735c12e486da01d3dbe64b2abd0c4456095c47b6fc5
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12061 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
36bb5e9e1a484b46ffe789b69d6dbe70ea4b4dacd361ff163f7132294218bc7e
deobfuscated-js PDF JavaScript deobfuscation pass 74865 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).