Malicious PDF — malware analysis report

Static analysis result for SHA-256 66fbf8472ebfad47…

MALICIOUS

PDF

92.5 KB Created: 2021-07-17 19:11:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 951c03cfdd27c0b68c9aa02611ca7be8 SHA-1: abd4fcd85bb76e54949c3e5d7327f7140394978c SHA-256: 66fbf8472ebfad479b1021ad2da86e7818d6e642f05f066d6c2d7fdbf3159175
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, which in turn host other PDF files. This suggests a tactic to manipulate search engine results or distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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 https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be6a1f2b6fa---68022104525.pdf
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/7eeb7b7e62b446674572f9ce4b3da258/kujatox.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b204df7dc12---denakivijasijaramodejuma.pdf
    • http://pressvaluation.net/userfiles/file/juget.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160823ed3ccd6a---62281512498.pdf
    • http://amadpich.com/userfiles/file/11202585040.pdf
    • https://roweryelectra.pl/app/webroot/uploads/file/1621197264109.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/96d74efaaf61b0f26a86e3e6ffb9c791/40067390534.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160874084224fa---24194517156.pdf
    • http://artpolinakuzina.ru/pict/file/64675842794.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cffa9acff5---77262204946.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b3f930904---80811121067.pdf
    • http://samtle.net/ckupload/files/82518020745.pdf
    • http://churchtextile.com/userfiles/file/76485912678.pdf
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/dowabusivetotibatisesopuj.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160edb982d88ae---lagujirizovupuvavubefuju.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607230ed2c85d---jibidulem.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/3v1ncvvn5jdqc38alpao13n791/bapido.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f4cd3d85b---fagevusizazoxegobikewu.pdf
    • http://yuha.be/_files/file/dexojevilijepevid.pdf
    • http://hoangnamjsc.com/upload/files/modoselejev.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/35c59fba973d8086b5533a388ec2eb7d/763791417.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=ethics+in+information+technology+fourth+edition
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00011ec4.bin
5a1fc1b90264e546832cc52b48abafe720ba4ca2897fa410bf90855477f6084f
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11EC4 23908 bytes
font_00_sfnt_off0000dbaa.bin
8f83bed9266684c115fa1f84e554acc64cfb25b28baf56e582f06d24ca0d325c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAA 16516 bytes
font_01_sfnt_off000106b3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106B3 16792 bytes
font_03_sfnt_off000148ce.bin
436c94de2488a0bcb1d894784188b7b489565368e77dad236cfac77c921e5f67
pdf-font-stream PDF embedded font (sfnt) at offset 0x148CE 11120 bytes