Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f550ca6a534e6cc…

MALICIOUS

PDF

83.1 KB Created: 2021-08-30 22:38:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 992eaeb2d0481bf93aa7777a10f24a2e SHA-1: 087d316ee4a96e169c4ed857e75d890bac819858 SHA-256: 3f550ca6a534e6ccc65adc0234bbfd1abfd89c3e364e7f9a665178b93e6e0cf8
176 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple external websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The malformed stream length heuristic suggests an attempt to hide malicious content.

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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 http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/33582221427.pdf In PDF document text
    • http://radis-rrl.ru/userfiles/image/7286262098.pdfIn PDF document text
    • http://greenbiotech.vn/uploads/userfiles/file/54058238451.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/9be13d99c162631db41acb0eb9318eb6/39538474331.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/29812732722.pdfIn PDF document text
    • http://drlanda.hu/user/file/mukimekozatazamutodew.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/27590757621.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/789vqq67oo2kn3c232rnbne2p8/fesenezisapiwatixawaju.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/gibedurijinezuxabidiv.pdfIn PDF document text
    • https://lbk-ingatlan.hu/uploads/file/33173748952.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/72332095931.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/57225762264.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/morirolurifuvanimelixeti.pdfIn PDF document text
    • https://smg.bid/ckfinder_userfiles/files/61243990050.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/1cee2f73577f3fd59a4cd85b7a7b4bce/degipejigugejubuwebaveju.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b3f7e7320---9193340289.pdfIn PDF document text
    • http://kashima.cc/userfiles/file/gewodaza.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/46809285491.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/danopixitonag.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e42a854433---81932149260.pdfIn PDF document text
    • http://trendybiz.in/usersfiles/file/26603596993.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/18535723863.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/b6c921175e4a0abd55b653ae270fbd21/mixixoxuletitikusim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=security+policy+restricts+use+of+cameraPDF 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_off0000deeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEEB 17460 bytes
SHA-256: 426144a1c41b4484a4feed143b2e26b663ad41c1c27b76aef7eba3fc3eb50edf
font_01_sfnt_off00010c9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C9C 10824 bytes
SHA-256: 652d2e26d739a8369226e3b075232298ac595951d487e2d8fc36798061142af6
font_02_sfnt_off000125a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.