Malicious PDF — malware analysis report

Static analysis result for SHA-256 c58213dba084e274…

MALICIOUS

PDF

89.9 KB Created: 2021-07-30 10:10:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e3274fbc229d0e069ca99badda07df02 SHA-1: 37fc037fad917e2c6c80618533b53e615e679ea3 SHA-256: c58213dba084e274e6e7c7ec8497d2303425fe044cb43b3744f4bbc6d3ef6027
196 Risk Score

Malware Insights

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

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains a fake CAPTCHA lure, a common social engineering tactic to prompt user interaction. The document also hosts a link farm pointing to other PDFs, some of which are hosted on compromised WordPress sites, suggesting a distribution or redirection mechanism. No scripts were extracted, but the presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea0eb064f5---14870036081.pdf
    • https://mimpiindah2.com/contents//files/60939470098.pdf
    • http://collegium-connect.nl/ckupload/files/64064202519.pdf
    • http://lycee-elm.org/userfiles/file/venogibomusamitopu.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/a0a1d1176cbb0abb3afb8953b2ebc7a6/46851934998.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/3daa36736a1ad423581d20043e533662/bonegikukedobolap.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/c62cfe4911ee5517a952c66a4a499256/63126291850.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc080bc853---kenaborafar.pdf
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/31pkndcafopdkvkrhs78va8cup/86934565053.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b33a285857---kozakerunijol.pdf
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/r3ii538u8lprjrdtatnjkc3382/47751368880.pdf
    • https://classconnbio.com/img-jacson/files/94027389885.pdf
    • https://muratay.nl/userfiles/file/27226604920.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160dc1ed81198b---77673657428.pdf
    • https://lacecinella.com/writable/public/userfiles/file/gobumoxerazapiliwixado.pdf
    • http://www.cda.org.hk/ckfinder/userfiles/files/12650714921.pdf
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/badowezadidogux.pdf
    • http://www.deewanalarab.com/up_imgs/93432743257.pdf
    • http://oxigensupplies.com/shipinc/userfiles/files/29666679859.pdf
    • http://abwlargo.com/uploads/files/24871236825.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777826a9c15---70241750152.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089ea69840d3---fofujakoje.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=fifa+16+ultimate+team+mod+offline+apk
    • 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_off0000f8a2.bin
76acf40c01e555e32ced19d3d1bd09a78a687bce89c0a2c62958a991a1db54f7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A2 18420 bytes
font_01_sfnt_off000127eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127EB 16792 bytes
font_02_sfnt_off00014002.bin
f5bfcc06ba42389a378c78e594aa26d1ff0974708ead63d5705efb7cac0354f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x14002 10780 bytes