Malicious PDF — malware analysis report

Static analysis result for SHA-256 97b50fbdccd3f70b…

MALICIOUS

PDF

81.4 KB Created: 2021-09-23 11:49:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d509268bf2714b11b85ac2001d0af56 SHA-1: f19180697d09fd342862c39b35d64840bfcf5a1a SHA-256: 97b50fbdccd3f70be4ce2035cad6a40def89aba7c61dcf22b1a820da3ce4d1ec
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links pointing to disposable hosting, suggesting a tactic to distribute malicious content or phish for credentials. The embedded URLs, despite one being confirmed benign, reinforce the attack pattern of directing users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://93564497.com/userfiles/6823168081.pdf
    • https://markyatirim.com/resimler/files/nolud.pdf
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/95390913527.pdf
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/xomodabikofagojaw.pdf
    • https://www.agencesramos.com/ckfinder/userfiles/files/5791328141.pdf
    • https://truyenskyt.com/upload/ckeditor/files/74019624313.pdf
    • https://khambenhxahoi115.com/images/files/26951574150.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/b519a08efa2d91b366c6eebaa49e0825/41802442709.pdf
    • http://shqinze.net/admin/upimg/file///giropemotufowiji.pdf
    • https://knoxvilleremembers.com/media/10646733571.pdf
    • http://nhadep30giay.com/uploads/image/files/38978421845.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/823300ce06aabafd57aa15276873219b/92962499989.pdf
    • http://fatfailogistics.com/fckeditor/files/file/rezodewebozexiwiman.pdf
    • http://forglass.sk/userfiles/file/37232958712.pdf
    • https://roshnaai.com/ckfinder/userfiles/files/sikur.pdf
    • http://precisao.net/files/files/50353680890.pdf
    • http://aligokdemir.com/resimler/files/47578271088.pdf
    • https://tfsroanoke.com/home/tfs/public_html/new/ckfinder/userfiles/files/65084836792.pdf
    • https://mgrenginiai.lt/ckfinder/userfiles/files/6653669926.pdf
    • https://okinawa4d.com/contents/files/14730034112.pdf
    • http://bpsstudio.hu/uploads/30968138043.pdf
    • https://medbioplast.com/klucharnet/images/file/13029175155.pdf
    • http://martonaroniskola.net/userfiles/file/bunafanopozez.pdf
    • http://hamdannepal.com/userfiles/file/nebisakigefoniriba.pdf
    • http://bhavalaya.org/ckfinder/userfiles/files/94908410107.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+do+ios+14+on+android
    • 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_off0000d52b.bin
f872f746942e0546a14e3600b1cb2ce2911b3d9fbb7109a70575d618ee2734b1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD52B 19752 bytes
font_01_sfnt_off000108b7.bin
a517ab7abf2cf4d65910ae23414b849927dc84333cadb98657e36b6a64f11fcc
pdf-font-stream PDF embedded font (sfnt) at offset 0x108B7 10272 bytes
font_02_sfnt_off00012005.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12005 16792 bytes