Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a0525c38fc3b570…

MALICIOUS

PDF

89.3 KB Created: 2021-07-08 04:52:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e09aa64535631075bf071586be993b5b SHA-1: c3cda43ddfc10bf6d1ca6255152f1fb1ec159a97 SHA-256: 8a0525c38fc3b5702784c50618caf454c034e778660077b4936b0cee1794db2e
176 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of a callback lure heuristic further supports a phishing or scam-related attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://skrabl.pl/www/rpbd/fck/file/losuvekal.pdf
    • http://kfnmdg.com/upfolder/e/files/20210604102546.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/77ivofggeme0fm19n65pqlejl0/2462021571.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608d242364953---92757141181.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/7e70d0d885c9d1b87c8e56124ab18d17/todubimisipanaje.pdf
    • http://akicgiyim.com/userfiles/file/49744658075.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/3551d75ee0b9332b7ffad7a3de441c3d/99563132183.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160943764e1958---79521934356.pdf
    • http://italiancousins.net/clients/5/54/54f3d33123424807706abe9154268524/File/32133233264.pdf
    • http://finpacecuador.com/userfiles/file/jelanus.pdf
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/0aur0pc10pbdcncvosojunqkg2/52715292722.pdf
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d83ec746a8---fonatijiroxezarugojesu.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4cb0c3bf2---39819391014.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608df81031dcb---sejuzemavetaj.pdf
    • http://phdpecs.hu/userfiles/files/fuduwuzunifovatesexejat.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3a5e0664a---58899561046.pdf
    • http://usagimatur.com/files/others/30537806444.pdf
    • http://polskienarty.pl/data/aktualnosci_imgs/file/70034105759.pdf
    • http://clinicaveterinariagoitese.it/userfiles/files/46581124894.pdf
    • https://noddy.nu/images/file/56127363307.pdf
    • http://unseenadventure.com/userfiles/file/suzazurejuvanitogikotis.pdf
    • http://cambridgekapurthala.com/damana/userfiles/file/9683645376.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/63fe241b4e8917869216e04073c62455/2567985762.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=thermodynamics+pure+substance+problems+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_off0000f8a8.bin
66380ed2937c262d4432230b3bdc0fa832261be43b96fd81cb783268991a8985
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A8 16800 bytes
font_01_sfnt_off0001245a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1245A 16792 bytes
font_02_sfnt_off00013c71.bin
96bbc2ff42c067fe3c150c591f3fcdc5d0edb1325d02bca48474caf6e44c00be
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C71 11200 bytes