Malicious PDF — malware analysis report

Static analysis result for SHA-256 991c383a78109121…

MALICIOUS

PDF

90.4 KB Created: 2021-06-29 01:11:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d49afac25eda8c326f5bcc42fd5689d2 SHA-1: b60985a665bc54e4af31f0bf41c0305207ebb60f SHA-256: 991c383a7810912150174f2241f956ff41e01600f93e4ef7d8d214e9db6d7fd4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file is identified as malicious by ML classifiers and ClamAV, and contains numerous links to compromised WordPress sites. The document functions as a link farm, likely designed to redirect users to malicious or phishing content. While no scripts were explicitly extracted, the nature of the links suggests potential for further exploitation or redirection, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://angkortaxiservice.com/userfiles/file/72506505101.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160751312a1d83---lakowokevenugumetuvelus.pdf
    • https://contabil-fiscal.ro/mm/file/dawuzoxogu.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/c38cb858667dfe12822e9f96ff414ee4/65704478887.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/c2b9cdcdd2e15d90cb103427df505a94/rolukafelotejadufinivud.pdf
    • http://vivaldiskibus.com/FileData/ckfinder/files/20210618_5A281DE80D2A5F78.pdf
    • https://cleaner.pl/userfiles/file/31795789597.pdf
    • http://perfekttorun.pl/pliki/ruvimujexupijaxuw.pdf
    • http://archinfo.ru/uploads/file/gogupurotavunadonipunaxo.pdf
    • https://conexusinternational.com/ckfinder/userfiles/file/loberu.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/e263a189bf0ab89bd033dbb79ccaf49c/33805331674.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608abb4e38cdf---93651987023.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6342db0b9d---nafokaxoja.pdf
    • http://angarakshaksecurity.com/userfiles/file/tazupesozojukomirawafo.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/q25md6sfkl9tp26u2eng2hn7ib/89726152340.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a15b7de9829---94856898612.pdf
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/a0c802d2ee6c29391167fd4d6f36c3b6/47928971618.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/6b1c17359337aedd6923faee6848c521/xonogawu.pdf
    • http://abacusnancy.com/userfiles/file/18941019424.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/710a2a6a62a2866aa1f8a777b4dc4ae2/solukemosojizugejuxiw.pdf
    • http://permianhighschool1970.com/clients/e/ef/efee9fcbc667252fc4b649c8163d3733/File/31224843110.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=webster%27s+new+collegiate+dictionary+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee90.bin
849d10f09dae5e2d6cfc8fb9993170d8f1e25d1c39619be8eefe8b48ce90a763
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE90 19100 bytes
font_01_sfnt_off00011ecd.bin
0f857459d3f09244b4d034349dd73b03fb52d61d8ed81d956356b3e388cef6f2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECD 1996 bytes
font_02_sfnt_off000127f5.bin
38026e98acf985e013ea9e16770d6ce55d742cdcb0db59349213af4948b89aee
pdf-font-stream PDF embedded font (sfnt) at offset 0x127F5 11160 bytes
font_03_sfnt_off000141e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x141E4 16792 bytes