Malicious PDF — malware analysis report

Static analysis result for SHA-256 a129e81d9a306e3d…

MALICIOUS

PDF

88.9 KB Created: 2021-09-20 16:22:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c84413511f91471d86d538866e3c20cc SHA-1: 936161eeaf4c6fc100d482020833bd993919d258 SHA-256: a129e81d9a306e3df4c28dbaad17d21ef78aa02883894ff0d5e77ff0e6afeb24
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links, many of which point to compromised websites and disposable hosting domains, indicating a phishing or link-farming scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious content or further stages of an attack. The presence of multiple links to compromised CMS uploads and disposable domains reinforces the phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161405050136a7---91578451958.pdf
    • https://ebal.ro/app/webroot/files/userfiles/files/13707820773.pdf
    • http://ayhancevik.com/images_upload/files/tosida.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/djto7q10ur6darlu57h4a13kik/66613649799.pdf
    • http://omgmediatank.com/userfiles/files/98045288412.pdf
    • http://abacusnancy.com/userfiles/file/dolejaviki.pdf
    • https://crownprolaw.cn/userfiles/Proj_Name/files/manerepefobisiwuralama.pdf
    • http://poornasreehomeoclinic.com/ckfinder/userfiles/files/jijafudufagor.pdf
    • https://rapn.ru/ckfinder/userfiles/files/xoxapagudon.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/86d7d607dbe6e1a4d52a6ccd6ed5d203/jozubuxew.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614302358614b---36758850714.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/cd79195c74c390424bf7aa0318239c12/gemewalora.pdf
    • https://transmar.biz/ckfinder/userfiles/files/vukejipemiremul.pdf
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/87969649874.pdf
    • http://hftyby.com/upload_fck/file/2021-9-2/20210902123535997596.pdf
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/4141144030.pdf
    • http://agcslohian.com/userfiles/file/xasufesegemukadabi.pdf
    • https://safrano.pl/userfiles/file/pufesepibenirudi.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132ab0862da3---gelezoboripirani.pdf
    • http://vhshf.de/File/bimimixasujanawiguzide.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613baff738a77---52498293544.pdf
    • http://regcureguide.com/files/files/81421223065.pdf
    • http://surmounttravel.com/userfiles/files/mixiwuxedojimotugig.pdf
    • http://pm-ural.com/uploads/files/zadizapilovelijimameru.pdf
    • https://tarzminder.com/resimler/files/nosotiwepokazezutisatud.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=new+english+movies+online+watch+for+free
    • 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_off0000f77f.bin
7d33e03198d57629358a87f3e4a31f71ec99ec8138f47a04feb509f6567f0e50
pdf-font-stream PDF embedded font (sfnt) at offset 0xF77F 10912 bytes
font_01_sfnt_off000110a1.bin
d3fb8b13c6227362c2b026442eeb8b00101ec0aa1c6e37d0170ca9365b09f2a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x110A1 17596 bytes
font_02_sfnt_off00013de2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DE2 16792 bytes