Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0e73c81e5b21cdc…

MALICIOUS

PDF

90.0 KB Created: 2021-07-16 12:45:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 116b6a26f526ca88def4161d1bbe2d92 SHA-1: 189b7489989c771075e98f659ff5a8ccd92c4dc9 SHA-256: c0e73c81e5b21cdc02b7961031bbfafbfc3c18ca77b9c3118ed08a9ff3fbcbd6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and does not provide direct clues, but the heuristic firings clearly identify the link farm nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://drafthe.ru/uplcv?utm_term=ring+shout+book PDF link annotation
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e59f7e9e34---22427953238.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/e6385ae7ba978984984d3c8e48eadb2c/mavudazenilidamonimug.pdfIn PDF document text
    • http://jarosi.hu/files/file/gefakojenulonil.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/99339116074.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/l8ll0itbsq01bpgj20od7g9rvv/1400009454.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c30b23b47---bumukenirepiv.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/3d99e9ca9fcf2eac03acde915642981c/gumopafikaritexixuzidubos.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b675ae82cc3---balokenimilurum.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/ximati.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/52007119607.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad80ba2355---ritebawinej.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9c2e694b9---86720347429.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/jewovusixevovijixixabimo.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608164196ac2b---25685681998.pdfIn PDF document text
    • http://taskentcompany.com/userfiles/file/25535100449.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/6eae9fcd1c2f3377f206e1d0b3902e92/1401321379.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/64197497315.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16082a372d3bbf---fifoke.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/ulbnr5u5sg7okh93deqs52k83a/sakepaloguxizakigubirob.pdfIn PDF document text
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/zevifod.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/36672364961.pdfIn PDF document text
    • https://mccartha-cobb.com/userfiles/files/72426191982.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607939a2d862f---foluzozularurar.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/673fbb53923c28bc3b73ad89e07de95e/61609376647.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/xofazo.pdfIn PDF document text
    • http://alanurturizm.com/rsm/files/82782285565.pdfIn 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://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_off0000fa87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA87 10324 bytes
SHA-256: 43c85c7692c468f1ea0440bfeb2476480d00004fd428b9400da0575e68f61d7d
font_01_sfnt_off000111bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111BB 18212 bytes
SHA-256: 122b06a28526ebed71251201f9cb6e6399416bf2489fa335b956a85360d4057d
font_02_sfnt_off00014148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14148 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1