Malicious PDF — malware analysis report

Static analysis result for SHA-256 109987a355c31521…

MALICIOUS

PDF

94.6 KB Created: 2021-08-02 08:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 33912eb31ad4080813ff806ca8d1bdb0 SHA-1: d227eb4ddea95e53bf2c3b5f7db827658bbbfc3b SHA-256: 109987a355c31521cacb3571f8bd3bcfd21d26228037373abab9d8d7cebc9893
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics identify it as a link farm hosted on compromised or disposable domains, designed to redirect users to external sites. The presence of numerous links on potentially untrustworthy hosting suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://clintonseniorhighclassof77.com/clients/e/ec/ec6cde7faca09d53f5ba1fe44cd32e38/File/gobefokizosofe.pdf In PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/5a988a2fb45b6fcdc3c75628b8ada99e/mexelidolikugedanofefa.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/1608294e8c9080---botelibu.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bd80140d7c7---sujobudut.pdfIn PDF document text
    • http://nandishoverseas.com/UserFiles/File/puwupixuzixekovumuva.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/xexafepiwelodisir.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096fa9895f55---73751640171.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/67bfbad6c811b2113e0779f2c566d053/wujujudezasizojekor.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/16087287270.pdfIn PDF document text
    • http://nensi.si/upload/file/vazufa.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080e2af6a548---situbokumumolibijenegone.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a588e25539---90943920142.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/f04789d23c6b57415c6619524bd49e57/xizixuv.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6f9bcac46f---nojaja.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/50521395415.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/ouh8pta3n1dbjktgv5ke12399e/27119524812.pdfIn PDF document text
    • http://didula.com/img/file/7862084881.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/5fa9159b85b4e270983cee56160f096b/fodadedabipoluforovat.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/6650097933.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/9507489234.pdfIn PDF document text
    • http://stpatricksreunion.org/clients/84553/File/5651141401.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///vanovaxutemukemokamuzav.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/jiwoberaku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=como+se+escribe+un+texto+descriptivoPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B6 10908 bytes
SHA-256: 4adbcca5f4f3a3a48cc21f7704f02d0bb67b9af4a35f4867d898ade60f8ef5ff
font_01_sfnt_off000121c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000139d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139D7 18748 bytes
SHA-256: 75a0c02f45dee42fb5c91209f89cd8adae62c0f55c79b18d16fed7f957ef01d3