Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b455d3e1f6c1ab0…

MALICIOUS

PDF

83.7 KB Created: 2021-06-28 16:14:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 403f4595629b6bcc64759e970fed1b39 SHA-1: 96409cca68031ff9ff8420b0bae115917a42c6b2 SHA-256: 7b455d3e1f6c1ab06acf9a25a7cd33fe5c98a1d48216dfd9e4214a80279b6c6a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or manipulate search engine results. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 https://annjulieskarpmo.com/userfiles/file/38472108516.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b76f0bc7539---86612378538.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5f80f3936---47757852444.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7259c1d7af---3921573144.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/l19k5m3fjaaljmenttq79vbhdc/bofefizufifajogitup.pdf
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cafb019234---3421978527.pdf
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607723a2089ba---fepiboxazipulop.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2f6ee4650500394cca13dc595a707d65/490270660.pdf
    • http://freeski.hu/freeski/file/73203192753.pdf
    • https://amursvoidom.ru/media/files/62662882220.pdf
    • http://ajtoablakcentrum.com/_user/file/18005602937.pdf
    • http://cancercareresearch.com/userfiles/file/pulaxanexozefilurob.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b09597a8242---lodolesedetifoxugoralive.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8d071528f6---91429011546.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/9346859762892aa9c4d9c89b8586e868/zumaxorazop.pdf
    • http://dancephoto.ru/userfiles/files/70953317899.pdf
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/dko56liq2r203r9dmq2keuc42n/76076007852.pdf
    • http://zxsolar.com/d/files/bekijagewado.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/pc15nf7ujebrbtga7ma5v33csn/zonefasezesatezenoge.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=list+of+abusive+words+in+english+with+meaning
    • 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_off0000e365.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE365 16792 bytes
font_01_sfnt_off0000fb77.bin
60d3d63b531d2a595e4f3886e04776a9ece7791af7027cee405c1d2101a33ddc
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB77 16408 bytes
font_02_sfnt_off00012604.bin
8797f397da1205f7b7c60a9d39a8972e3a6940bb92258861f7a3ed73123b5f84
pdf-font-stream PDF embedded font (sfnt) at offset 0x12604 11148 bytes