Malicious PDF — malware analysis report

Static analysis result for SHA-256 85bdf7d9ff245ac1…

MALICIOUS

PDF

92.2 KB Created: 2021-09-18 05:28:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 848d5225f76009cd5f13466d01b41cc0 SHA-1: 8184a01578dc6b4bb4d7f6696b885d6bb451c26f SHA-256: 85bdf7d9ff245ac145e1682383947f0dfa66128581fbe28454c79a3d21004706
156 Risk Score

Malware Insights

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

The PDF document contains a link farm with numerous URLs, many pointing to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9921

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://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/lmqc0572dtvh4assn60292vt91/gusapevirelekosabe.pdf
    • http://lignumweb.com/site/webroot/uploads/files/padixipi.pdf
    • https://asoriofrio.org/ckfinder/userfiles/files/38251173160.pdf
    • http://pol2-simf.ru/userfiles/file/55802639652.pdf
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/jamupiwume.pdf
    • http://a1-automotivegroup.com/upload/files/27275935884.pdf
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/18356018952.pdf
    • http://gammatradings.com/userfiles/file/wolobigevaw.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132083a09b5a---25025388394.pdf
    • http://rickgrisolia.com/userfiles/files/veteziwabi.pdf
    • http://xutricolor.com/uploadfile/files/bilutedovo.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/e9687dfdf4523156def9a6c879298dd7/fanazem.pdf
    • http://www.fonfe.com/uploads/files/jesupemerogajigimamizef.pdf
    • http://kondicionery-vidnoe.ru/upload_picture/file/fawenofol.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613480cc1f54f---90372277219.pdf
    • http://wolfroccatiassociati.it/userfiles/files/mavesisozekamajogopive.pdf
    • http://impex-italia.it/userfiles/files/54433415598.pdf
    • https://cgeminfos.ma/upload/file/22042043525.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/d5b6e603de488461866c32372bce80c9/72480013090.pdf
    • http://lngpetro.com/userfiles/file/81258955285.pdf
    • http://gursakaryahukuk.com/images/file/2777651975.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=hack+stickman+skate+battle
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613caae341893---tazimekiwozosedesisedud.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc01.bin
c19d28709377d8222303e93ca91e8cab9ff6d292fd90e2eeb5ab8fe6cecabd28
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC01 21820 bytes
font_01_sfnt_off0001145a.bin
345eef88abe24f23a49621e6df8a38883e48dc418f3976e27eba0b827bb73916
pdf-font-stream PDF embedded font (sfnt) at offset 0x1145A 10396 bytes
font_02_sfnt_off00012bd9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BD9 16792 bytes
font_03_sfnt_off000143e6.bin
6c08887b596ecb472c5a0482df8c2f828d83fc5b5d16111ed0caa1fced1b35dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x143E6 1680 bytes
font_04_sfnt_off00014bdd.bin
65dfad125546efb8f2a71f825911919546a9c7e51d723d910fc09019f6959011
pdf-font-stream PDF embedded font (sfnt) at offset 0x14BDD 16284 bytes