Malicious PDF — malware analysis report

Static analysis result for SHA-256 f89b91795816349f…

MALICIOUS

PDF

72.9 KB Created: 2021-08-28 09:26:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a61379ac3e0f8f0861721b323c2921b9 SHA-1: 3657906437963df074b45184cb13f812a2d3e25d SHA-256: f89b91795816349f387607e33b095fdfb2cb3188c0bf77208e9795ff18e474b6
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a link farm pointing to multiple compromised WordPress sites, likely intended to redirect users to malicious content or exploit kits. The PDF structure itself appears to be a link farm, with numerous distinct hosts and URLs, some hosted on compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://lycee-elm.org/userfiles/file/81209247939.pdf In PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/b9a7fd04ba0b6601dcc1565e408aadeb/gijamidebe.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/gonudugubezak.pdfIn PDF document text
    • https://bnovum.hu/downloads/tubanebebitelatowerovuso.pdfIn PDF document text
    • http://solmoda.it/userfiles/files/14404770542.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/5oeq3l3v0ogg0i9k14uhp5ia2t/garij.pdfIn PDF document text
    • http://klassn.com/ckfinder/userfiles/files/2820357650.pdfIn PDF document text
    • http://chinatriage.com/ckfinder/userfiles/files/14181092793.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/9851e96e10895c3f6b17f24e6fdf30b8/19301811042.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/momepom.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/65892541796.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/1b53c502efddf3ac02c175bb06a986ff/zuweba.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160befedd43a5f---23095113238.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/54224463259.pdfIn PDF document text
    • https://morethancars.eu/uploads/edytor/file/67074496374.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160786f7e52c20---lawinasixiw.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ae3eb6f50---gagevazagovalarax.pdfIn PDF document text
    • https://oversaslogistica.it/file/kopenoliladixegu.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070d98e53adc---49339304791.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/84026906881.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16071fb93984dd---nebituw.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a971018ed32---42002036659.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/kajupo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=saline+soil+electrical+conductivityPDF 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_off0000b8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD103 10716 bytes
SHA-256: 6705243f39aa5c9371f38df9f55400c6a6fe452c98fadfdc05de91386fe54f24
font_02_sfnt_off0000e9bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BF 17120 bytes
SHA-256: fe3fc5bbf3ed4cecda8361dbb3727875b49e91fd8074432238a92f0c9b073d2c