Malicious PDF — malware analysis report

Static analysis result for SHA-256 79f869ba49d28476…

MALICIOUS

PDF

82.9 KB Created: 2021-06-25 12:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: bb0906e46979dabf77ac10abda6a11da SHA-1: 228f7e73e49b4aca37ce0fd4b90de2689ce36711 SHA-256: 79f869ba49d2847686d11eb383d834ff461a726003803188a930bf43bdaf796b
96 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and embedded URLs suggest an attempt to direct users to potentially harmful content or exploit vulnerabilities through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160758110ba557---29607464326.pdf In PDF document text
    • http://diversecityuk.com/userfiles/file/pogamuko.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/779dbe9e1b14022fe8c36e218a2d8be3/nadukuriguxegus.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075a79580574---41791448479.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160a194d1e41a6---volopo.pdfIn PDF document text
    • http://giaoducvietnamtv.com/images/ckeditor/files/podekavubotu.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b489b7d8ef0---japedo.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/2c7a69d8a80da928a0a004b1852cc429/96683016693.pdfIn PDF document text
    • http://babamoleskine.com/files/file/wivexovomo.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/df5037806a5f3084afeea1a6e772c60e/8385212421.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16099ac0d01715---7233894460.pdfIn PDF document text
    • https://napraforgohotel.hu/upload/file/91810211924.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160767fd3561aa---jureposar.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/uacu8hbeqri0tg19bo70tgr2n6/79441332529.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16098f209c0cb3---33922284461.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/tidakomojenuxavuwovakavo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=english+horn+double+reedPDF 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_off0000e292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE292 10488 bytes
SHA-256: 5841418ca8db7b40bd4545318b62dfdde4b953c403164207afcfc0727e5ada87
font_01_sfnt_off0000fa01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA01 17560 bytes
SHA-256: 3e58ab5d4a88bf1a299c4964032efce2c9c3d73c4594ab74851b56ee0b78fea2
font_02_sfnt_off00012723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12723 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1