Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c134e8abe3e7a86…

MALICIOUS

PDF

85.7 KB Created: 2021-08-15 18:32:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8a8d0e6e6f1386657efeefa5ad8dd44e SHA-1: 51afeb612ee2d0bf3df9c20692ba4b3c100fa260 SHA-256: 1c134e8abe3e7a864bd3daee84554f8ad7643da8cf9679c8645db17baf0dd89b
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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 http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160bf88e48ea5e---jufezexirukub.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e0df7d26c9c---gokunuvapefodiwetul.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/3ae2af3877db0d4cb3bef9f4d763327b/84668595490.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160745a64ce982---xesovererodixosobo.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16083ad9343fc0---vewumafowexurerovukamatip.pdf
    • http://thementalhealthadvocates.org/files/userfiles/file/29885507732.pdf
    • http://czdashan.cn/uploadfile/file/2021050909343773499.pdf
    • http://vejwun.cz/images/lotuvasokofigepikigumu.pdf
    • http://curry-box-deluxe.de/userfiles/file/rujupakeruvameduna.pdf
    • https://petek.biz/resimler/files/16690280939.pdf
    • http://atut-biuro.com/uploaded/file/21274049760.pdf
    • http://hoadon-dientu.net/images/files/63454735288.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/eeu26loup7hp84ajr92f4tqk23/75370634549.pdf
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/g9jm883jb2bicksdftv521kp20/95586830636.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5ccef1d44---pusebotifanofipekavu.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/974fdab73644518e2bab6521959c8f76/xajixokexenisokopu.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbe82eb3fe---tuvakarawoso.pdf
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/56945151437.pdf
    • http://luisacortesearchitetto.it/userfiles/files/sivarujesum.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4fb3707d7---62677715668.pdf
    • http://derkwoo.com/upload/editor/files/kidomozuvinavobixesoz.pdf
    • http://viettincapital.vn/upload/files/mijogilonuxetuzilila.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=adjectif+possessif+exercices+en+ligne
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7ad.bin
9215d5b34d283825e0c2b5494ad0c8819655c4c421d8cbc4ea56af88417e1ad1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AD 18596 bytes
font_01_sfnt_off00011625.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11625 16792 bytes
font_02_sfnt_off00012e3c.bin
6cdbc32fa3e928be29cb88b6b82b6afb02a03886b1389e70cbd847a1140c699a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E3C 10848 bytes