Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cb71869126f6310…

MALICIOUS

PDF

85.8 KB Created: 2021-07-28 06:18:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f1d1981821b8f7884c5574c3320248e8 SHA-1: 2ab00295ada278169b270885d044daf14a69fae4 SHA-256: 9cb71869126f6310e3f4256aedaa88fdc5ae40c60fd43e9c49fa7838d6096313
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress installations or disposable hosting, indicating a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c5921898ef1---riritolobojej.pdf In PDF document text
    • https://wagaskar.com/media/rafezaxav.pdfIn PDF document text
    • http://veterani-pushkino.ru/userfiles/files/guxawibit.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a89ae3f3b52---ritefobozezowijatixa.pdfIn PDF document text
    • https://castel.ro/userfiles/file/92366211550.pdfIn PDF document text
    • http://yilip.net/userData/board/file/18465789928.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/nugaxure.pdfIn PDF document text
    • https://unibel.pl/pliki/upload/file/rozemuxulariwenaxanepu.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/43322842720.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/3naghvmd02omspjva80edbj7tl3c1s1c/pavalelizewarodegibima.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160baaf231462c---belugibidilaxowebegovifir.pdfIn PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/63452770892.pdfIn PDF document text
    • http://alexanderkanevskyartistbiography.com/clientMedia/file/metebaj.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607851892f101---77849148746.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ba92128562d---55238915216.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/5485a4bdd4c96f55feea026ddd1d4be9/32610979932.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/kaduz.pdfIn PDF document text
    • http://appletechsolutions.com/userfiles/file/28828498954.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/4906da432d128faa27400ee06557d93b/ramokezojoliranuxisezewiz.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/psvf2o9uende9rfmn3nkiq07g1/54191057024.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/vojavelajamejefezeji.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/rv0644btuavvaumes7sspst4hp/60510426785.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/ge2sjr5qtmdaos3ril7lg75smg/jewuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=engineering+assistant+syllabus+pdf+2020PDF 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_off0000ebd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBD0 11132 bytes
SHA-256: 8345d3fd4acfceac87129da98adc4bae8b96d293f7180e804e640b810bcd246d
font_01_sfnt_off0001058b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1058B 16736 bytes
SHA-256: c6215d6ac392a628a88e1727dc53093bdd37f3a33357eda5a11ce2606e029e66
font_02_sfnt_off00013121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13121 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1