Malicious PDF — malware analysis report

Static analysis result for SHA-256 55d5bb162a21e68a…

MALICIOUS

PDF

86.6 KB Created: 2021-08-15 20:23:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c825923754f220503e06620b41ffb224 SHA-1: a83e1751dbec513d9a092ba9a7eb30d57b43fe93 SHA-256: 55d5bb162a21e68ad96598b4b3bfa589f75224a5a2eafac6b75ced3ede587d3a
156 Risk Score

Malware Insights

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

The PDF file contains a link farm that redirects to multiple domains, some of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns suggest an attempt to lure users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9896

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.jindatunnel.com/up_files/file/69512972844.pdf
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/ua1hmelptne6u4a3h5s2bd2ga0/noxiporolaw.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/a306414c7658f415e1fea7450c595bed/1230097540.pdf
    • http://balbu.hu/uploads/news/file/2459969004.pdf
    • http://sllight.ru/design/img/upload/file/datekeburimi.pdf
    • https://amrapalispot.com/userfiles/file/bikoruwud.pdf
    • http://namngonviet.com/user-/files/58820956018.pdf
    • http://architettoseneca.com/userfiles/files/xurufekekafulono.pdf
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/24758933500.pdf
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/bfb8f2e3b42b05163dabc2fa6658af00/33520371372.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/c44939a42ab7014438b1d7fadbd78c69/nirazeginiwanugevalobe.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/haqkb0ilb5fhukgu0gjsks2oq3/98114300796.pdf
    • http://www.chp.pl/ckfinder/userfiles/files/tevubiden.pdf
    • http://ebslang.net/_UploadFile/Images/file/19959693983.pdf
    • http://porpora.eu/imagenes/imagenes_contenidos///sujabojirebanamudepuzaf.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cad9ab6f0---terive.pdf
    • http://progfin.pl/userfiles/file/sewemugakafolopomejimepi.pdf
    • https://europartner2.pl/uploads/zagukurijuwulevur.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/41b3cc5052320906794b3529e76061cd/pagemaw.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609d32a973cf5---nufusavel.pdf
    • https://vientangluc.com/upload/files/63758570853.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a14e148d6---joxutomevaku.pdf
    • http://ototavandosemesi.com/resimler/file/48314475177.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/cb52e16344b6511a76a8d83f8ea30865/40864904627.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe88cedd05---44762575958.pdf
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/4232c5653ef122d418c89900aae6d306/lesitedig.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/3ce1c7c0309009b953a91c5c70b68883/wijibel.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=should+the+electoral+college+be+abolished+dbq
    • 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_off0000edf7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF7 16792 bytes
font_01_sfnt_off0001060e.bin
72731f80566114b9d358a3232170a1791e2c091176793225c626f53d2aca3425
pdf-font-stream PDF embedded font (sfnt) at offset 0x1060E 11008 bytes
font_02_sfnt_off00011f37.bin
1d5dec842e897e3eabdedaa347f71ad65a1ba13e9c44569fceb3a7d5418564ea
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F37 16900 bytes