Malicious PDF — malware analysis report

Static analysis result for SHA-256 81e8fe5f126183e1…

MALICIOUS

PDF

82.1 KB Created: 2021-09-20 18:28:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 16cc763ef292c326a0f833ee4d7f7b48 SHA-1: 328f634a26ea544b3ce28218588fbb5e737a29e3 SHA-256: 81e8fe5f126183e16a2f53efd39e6b31bf5f22a7fce8d3d2ddc83818c14dc8d7
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a link farm pointing to multiple compromised websites and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of external URIs and a link farm indicates a likely phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://alstar.uz/images/shared/file/39989619492.pdf In PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/2b2a3a426aa8fd5cb38357d624497b90/32357091911.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134452384f29---27889076815.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/samukonoritubowewaxes.pdfIn PDF document text
    • http://land89.com/ckupload/files/15908826866.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/25683958190.pdfIn PDF document text
    • http://belv.ru/userfiles/file/bepubosokusuzegop.pdfIn PDF document text
    • https://tecnomatec.cl/upload/file/88375817633.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/95573737194.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/f0add87c377dfdeec27216328f561367/70127775366.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/tefemigobasikolijakefane.pdfIn PDF document text
    • https://dm288.rs/slicice/file/nemukutidojonovepajozi.pdfIn PDF document text
    • http://taispacedesign.com/upload/files/81046865277.pdfIn PDF document text
    • http://goldway.jp/upload/board/file/saxoxinegole.pdfIn PDF document text
    • http://ryukatsu.com/userData/board/file/14337595224.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/88798508421.pdfIn PDF document text
    • http://shiraz.sk/ckfinder/userfiles/files/badadakorub.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/58976877211.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/62627185203.pdfIn PDF document text
    • http://tincorner.vn/uploads/files/42521387356.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/23294554122.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/32967628966.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ed07cad34---24690673930.pdfIn PDF document text
    • https://weboonline.com/ckfinder/userfiles/files/tejamakezez.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/lidowilavemepalolid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=apps+that+show+who+viewed+your+profilePDF 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_off0000d8f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F9 18432 bytes
SHA-256: 37c382de4f1c3900870fdb9ea48d25f63af7564dc1f3100bb5dc981de529704a
font_01_sfnt_off000108dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F3 10836 bytes
SHA-256: e7f03dc879be117f39e734ad9815185c5dee545889dbd329c44cbe42cf08c598