Malicious PDF — malware analysis report

Static analysis result for SHA-256 7873f46cb3276ea6…

MALICIOUS

PDF

84.7 KB Created: 2021-07-07 15:50:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d35780e4223e28f333f7bb357e6b1972 SHA-1: 368623dd7e0b39144457518b357eaec0dabc6ce5 SHA-256: 7873f46cb3276ea68e821f8b2157fea11009226b1a247327f300c71fbcbf6321
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to compromised WordPress sites and disposable hosting, likely to distribute further malicious content. The presence of embedded URLs and the 'callback phishing phone lure' heuristic suggest an attempt to deceive users into interacting with malicious links or phone numbers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • 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://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160926a695191b---15838995437.pdf
    • https://ajur.rest/uploads/userfiles/file/70066945684.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/aa6bb77ab39f94a29c80857fbc44ebf7/gatujibubosinozafozez.pdf
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210615042527.pdf
    • http://unicaconsultoriarh.com/images/files/7227533371.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a8223408a---wojezinazepopujer.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8654dc3795---sebokiz.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d69cf3a4fd6---58464421857.pdf
    • http://tubietelbar.hu/uploadfile/25670722190.pdf
    • http://rydelko.pl/userfiles/file/2148489975.pdf
    • http://oishisushigd.com/uploads/files/momezipuja.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/9c4d5ee1239954187e2890eac52e6947/zewafujetevif.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160719fd56daf2---76018102631.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d7c94c1459c---57317496982.pdf
    • https://dnsbp.com/all4help/fckuserfiles/file/20191480085.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/4bd7a8cc96ecc8787025d8e7aa848659/3021792487.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c7aae1248f4---4860925147.pdf
    • http://tubietelbar.hu/uploadfile/34610245219.pdf
    • https://malashealthcare.com/userfiles/files/refokuda.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/49f2fb063bdb51e2beeee88c782be6de/vagepux.pdf
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12840399143.pdf
    • http://smartcevent.com/clients/871459/File/pexafilik.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=horse+riding+poems
    • http://e1pl2.nazwa.pl/busy/fotki/file/pijal.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_off0000eb76.bin
a8827e3fc660dbeb8c147970b721a345e28d6bc09e26e1e52c62515cfad93402
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB76 10420 bytes
font_01_sfnt_off000102b8.bin
ce5e6ea9d94a1f1f8b8f9c90a74503d772468080b7397f3cc5546695f6f27328
pdf-font-stream PDF embedded font (sfnt) at offset 0x102B8 16644 bytes
font_02_sfnt_off00012da2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA2 16792 bytes