Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef4a110c37913049…

MALICIOUS

PDF

85.3 KB Created: 2021-06-27 08:19:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1220a91bf0b0065f782967db2f8a7212 SHA-1: 7c75a25af92b8fd0961454e177a9cbb561359741 SHA-256: ef4a110c379130492df510139d4a6ada355f9240d962f0ec45b3ac8f0b330fcd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories and disposable hosting domains, indicating a link farm designed to redirect users. ClamAV detected this file as Pdf.Phishing.Trojan, and the ML classifier also flagged it as malicious. The presence of these links suggests an attempt to lure users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://abofahed.com/userfiles/file/ziviguletezulu.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae936b78f9c---domoluzo.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160739095d92e0---melakavepoliboxaturum.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae78ada4eec---71618029433.pdf
    • https://twinslock.com/ckfinder/userfiles/files/mexaluxalos.pdf
    • https://onhimalayas.com/ckfinder/userfiles/files/vubopekab.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abab10289e9---78856847675.pdf
    • http://omonetach.pl/foto/ilustracje/file/devipigemiwelokovijo.pdf
    • http://www.kickcommerce.com/userfiles/file/lajis.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c866d1135---mitisokasuxesopoweni.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbd2542266---velawamunisutosejili.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc48d33a03---dixupenotojumel.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160963dc1b251b---10520622227.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/zavupolemizesa.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a64761b94ab---jaxidejosajewejavidasu.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/1fa651604d718dc1f221a5b3735e830d/87145977098.pdf
    • http://amoy-art.com/Upload/file/93463697755.pdf
    • http://casaatlantida.com/userfiles/file///20940911101.pdf
    • https://ivanda-commerce.hr/userfiles/file/vabetutomubonelosetoxulo.pdf
    • https://kurtoglumob.com/upload/file/maramedeno.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd20a48655---73176004380.pdf
    • https://actorconseil.com/files/file/72239804498.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/h6p7tv57kfcfrajb97ha5ktlqr/nadiwexo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=clean+room+technology+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea84.bin
cee6a5fc76372805d2da4806de453cf09eb580156f3dbe360dd9e8cfb16f5f00
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA84 10952 bytes
font_01_sfnt_off00010393.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10393 16792 bytes
font_02_sfnt_off00011ba5.bin
6afdd1691ac7d732065c782f0776d6ae4fed937a06f87df143d79240130c95f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA5 16980 bytes