Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0493ffca8bf65a8…

MALICIOUS

PDF

78.1 KB Created: 2021-09-26 20:51:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e9df6185ca744c04d8bf349a92763d5f SHA-1: 9a7797360bae1cf86fb584717a7dc21d45cfd6d4 SHA-256: b0493ffca8bf65a869786aea3bc71cfe29e17e9637313cc67761b5b1755580a3
146 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm and a callback phishing lure. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of numerous embedded URLs points towards an attempt to redirect the user to malicious content or phishing sites. The SE_CALLBACK_LURE heuristic specifically suggests a pattern consistent with tech-support scams or billing fraud lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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 https://prospr.fr/ckfinder/userfiles/files/dabikewepoloburaziperenu.pdf In PDF document text
    • http://macautemple.com/userfiles/file/kaluvuk.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/ligewegonugesoz.pdfIn PDF document text
    • http://canshu.dlzj.net/upload/files/20210902105541538688.pdfIn PDF document text
    • http://soles2walk.cz/data/file/sexararebumomilowuta.pdfIn PDF document text
    • https://network-italia.com/file/xamobawozozup.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/93092795340.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/16118799526.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae736477bd---33317842368.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210921071144.pdfIn PDF document text
    • http://tokyo-sanritsu.com/userfiles/file/xelotavarug.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/83906963173.pdfIn PDF document text
    • https://aneri12.cz/res/file/wesipiramur.pdfIn PDF document text
    • http://alhegazgroup.com/userfiles/file/24889073293.pdfIn PDF document text
    • http://traviet36.com/upload/files/79304977852.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/6e3tdh0gvt5e4o7ppe3av48f25/xipokalidabasajewonov.pdfIn PDF document text
    • http://www.bash.cl/media/file/bileralaketi.pdfIn PDF document text
    • http://seashinechina.com/admin/fckeditor_upfiles/file/2021092601225480554.pdfIn PDF document text
    • https://csn-alliance.com/data/files/61992649843.pdfIn PDF document text
    • https://grouptm2.com/contents/files/40780166241.pdfIn PDF document text
    • http://kompassztuki.pl/Image/files/kamoreforiwisuramafukiw.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/3570358072.pdfIn PDF document text
    • http://soepcentrale-dekeyser.be/userfiles/file/83093632057.pdfIn PDF document text
    • https://solturism.ro/images/file/32049310565.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=android+automatically+connect+to+home+wifiPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c39d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC39D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAF 20552 bytes
SHA-256: 9b0aa79b9ddff3c3fa1c35cd0bbb289920c8308cade50bfdda3c60a0c44a32af
font_02_sfnt_off000111cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111CF 10852 bytes
SHA-256: 0b8d3f258bb4e8b981be2b37626398dccb46538d5cf3557154caf4e88b989de7