Malicious PDF — malware analysis report

Static analysis result for SHA-256 c952ad7d65a77dc5…

MALICIOUS

PDF

79.0 KB Created: 2021-09-12 08:44:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 075efb07cce82fb1fd2978c47720e334 SHA-1: 2411cd0dc474b8b06d338e7f0b3301628d230147 SHA-256: c952ad7d65a77dc572107c452c15b68de8d829de6b196c2537120650b46a33cb
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. It contains numerous embedded URLs, many of which point to disposable domains and are part of a link farm designed to trick users into downloading files. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://synerhu.ru/uplcv?utm_term=caxo+app+download+apk+latest+version PDF link annotation
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/35236115332.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/lobowosi.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/35336138845.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/19860826634.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369eb55ab51---kubafodatujube.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/87764307233.pdfIn PDF document text
    • http://ecole-belair.com/ecole/file/89737427509.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/mifobarabitinakefanep.pdfIn PDF document text
    • http://healthywithhart.com/res/file/wuzibigozowometap.pdfIn PDF document text
    • http://isvpro.com/custom/files/rupivowijiruzasazerub.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/siwijinejakakubesosumokus.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/jipewefozujapokovemixese.pdfIn PDF document text
    • http://nawooelcs.com/upload/userfiles/2021/09/files/210901081929.pdfIn PDF document text
    • http://hp-cnc.de/uploads/files/gofoxojabatodopojoluludi.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/vemukugorisobutadafiku.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613023ad6e32d---45910904546.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/litonurirarumumovaku.pdfIn PDF document text
    • https://klcmekatronik.com/ckfinder/userfiles/files/sidefuwofuvujojarus.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/xuvelomunubovaze.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/zuzixovo.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/nanafazabepej.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/44521298814.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF66 17976 bytes
SHA-256: 854e6f303bc2000a65029af60ecc1a26b6cc1ebaba35e07b3ee50200cca0001e
font_01_sfnt_off0000fdc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115DB 10764 bytes
SHA-256: fa11e0b28c19af4a61c558728af907978c1c21ccd0f86c895a6e1dcc355512f6