Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfef6e6ecc338461…

MALICIOUS

PDF

76.8 KB Created: 2021-06-25 14:11:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3629b0fcc1064da4fa32c537ddff2880 SHA-1: 4d56c84188b40439f2b227687609e58069bb0e26 SHA-256: dfef6e6ecc338461442d618c86f39201e35be5e3482865b46d37775824df27fd
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories, suggesting it functions as a link farm to distribute further malicious content or phish users. The presence of multiple distinct hosts and the use of UTM parameters in some URLs further support the link farm and potential phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/442309b4d98f6343fb088f9409127be8/jawir.pdf
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076acc313c78---tatijabujafewit.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/7864ac57bc2682f0e9f093e0e1c2b847/74080944863.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c125abda99f---40144691733.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab9c2fdccd9---63128962920.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16079119ff27d1---6195054890.pdf
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/04ef8427160a69ae1abaf9d305d8a394/55893879576.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16095d8c2c10a8---75082032019.pdf
    • http://curry-box-deluxe.de/userfiles/file/22299421408.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/1381aa7c81bbf4ebd44ecf9449ee98b0/4096663703.pdf
    • http://atenngo.com/admin/sites/site/documents/91461314069.pdf
    • http://aeronautike.com/userfiles/file/79915928436.pdf
    • https://codecs.ro/images/file/nireboxijozabu.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/c022608251f62492cc614e40bac47c31/jajurujezapapaguguzata.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a143c2e9a---kixujadinujusakade.pdf
    • http://merlegdoktor.hu/tmp/lipusiwaxiweno.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=new+mod+games
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000107f1.bin
cb316201fcdf5a28b7dfcd202497a5e513aa6620d5ea608b798cec4977f52ea3
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x107F1 18176 bytes
font_00_sfnt_off0000b018.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB018 16792 bytes
font_01_sfnt_off0000c82a.bin
f582b32f4c8def637ba699e39c8909d4d4dd00335f973441a9771ccb6261c965
pdf-font-stream PDF embedded font (sfnt) at offset 0xC82A 15944 bytes
font_02_sfnt_off0000f12c.bin
1e2e93e9b57d998e66d8592706ad41c94447881e98266ef2fd0f952848e02677
pdf-font-stream PDF embedded font (sfnt) at offset 0xF12C 10212 bytes