Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a982a3fe2e5192…

MALICIOUS

PDF

73.6 KB Created: 2021-05-28 01:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 958d8514e11d496499517f335b2a0c40 SHA-1: 7ee90f50d03b3c596cef6dd3b66894e861f36d0e SHA-256: 88a982a3fe2e519294698e08e2d46086fc7f7dd0923bb2996c06331845240334
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to compromised websites, many of which are hosted on disposable domains and utilize UTM parameters, suggesting a link farm designed for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The document body, though heavily obfuscated, contains text related to free music downloads, which serves as a lure to direct users to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://irlanc.ru/uplcv?utm_term=thamburan+ezhunnalli+mp3+song+free+download+in+malayalam PDF link annotation
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160809b74039e4---joxafulafose.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c223469162---luduvazifefaf.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16070d65ad1018---jizenataporef.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/vt34ep7j3lh7gbpf3m6rt6arp2/27542078489.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/91bee4c8bf71e54c320ab7b7c8ccdc8c/40111071030.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/cb0c690d84293ec0b9bdf2466585f16a/nufululubim.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160713d4694422---jejabixoberude.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16089aaa46c8ba---zaxusefiju.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609860cf80621---sekexuvigazorid.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16090e6883d07d---vilokezewijefumo.pdfIn PDF document text
    • https://unosms.us/userfiles/file/15088171670.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16074d386417a3---nesusokitosolop.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/79079828473.pdfIn PDF document text
    • https://isleo.com/i_photos/file/vilijetowuravuvomup.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/pakegore.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/b3c99dace331a858b97cc56fda8f09e3/57662691522.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e041.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE041 5952 bytes
SHA-256: d9a06c7a751408a4ebd0f671917a3c883d3f362259f3ce8b819e4bcf629bd18a
font_01_sfnt_off0000f471.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF471 10680 bytes
SHA-256: 2ed12b3e7b51c2f0a450c1a835ac6e42edd7d08b1b9da422700d8975a5d9cc4c