Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a904121bdd28d47…

MALICIOUS

PDF

88.0 KB Created: 2021-07-02 01:36:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 883d7ca34d68906ea05a6a99173df8c4 SHA-1: 3f8db19f81c0f2e424889b79b1d241d26701b0e3 SHA-256: 6a904121bdd28d4764cf09035f71fba6aae9be34d2702ec3dd3afecac2a35b6b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or engage in SEO poisoning. While no scripts were directly extracted, the presence of numerous external links and the overall detection profile strongly indicate a malicious intent, likely related to phishing or malware distribution.

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://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/185ae3478953f5dd5be4ba745705a90b/44347773536.pdf In PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609bbd53695c1---37909445228.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d40584fda4---nomagesakarazabosozif.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/c557l5ss9uh4c5cf3gt65gg8u1/wimilusisorowape.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160d851150a3bc---kefet.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077c10d6cd45---pibusezemosavowuvogusob.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a176578c7c3---wadumule.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088af9f223b6---rudimulijexegotiginexoga.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608731039cb90---wivobisojaj.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/72872961928.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/61409012660.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160daee2a2c260---78124998141.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893c77c65a0---biworozimitiza.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c65683b491---58685755875.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/tuvokozosu.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/2d9ef06c3225b7b6b52818f8d1a81541/64407558380.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607df314e94d3---jugajowuxitifopujonol.pdfIn PDF document text
    • http://erbaytag.com/resimler/files/kogixukugunikakisop.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/11a2412c575e0838d329f404ac14a6fe/bajitogowelam.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d312e068d---gobesisux.pdfIn PDF document text
    • http://logo4you.dk/userfiles/file/85940375750.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/871156806226a455111843a59eace81b/vamejiporunogegudanomivut.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/49256452886.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/ro3b8lri58vgo3s2qvje7ret74/54310982450.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7ce1eb94c---vedefelugopur.pdfIn PDF document text
    • http://lyjclinic.com/ckupload/files/81412036705.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=medical+laboratory+technology+multiple+choice+questions+pdfPDF 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_off0000f160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF160 17480 bytes
SHA-256: 0881ded517ed08195f3fbbcffac4535d65ac51f48129b50320bc27b02cb38554
font_01_sfnt_off00011f6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13785 11560 bytes
SHA-256: be296b0a7e39bff67bd67bf663629aaa458937ea673afd92f5e3eecf168aab92