Malicious PDF — malware analysis report

Static analysis result for SHA-256 4051fec804e125e9…

MALICIOUS

PDF

69.6 KB Created: 2021-09-26 14:51:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ec130598e247e8bbf35b941a9208f1e0 SHA-1: ad7be91689d7504d477a9e812197c05475eb02b8 SHA-256: 4051fec804e125e991b2f88c7989c12963225849d04e15b0ad9626f8995d5406
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as an image-only lure, a common tactic for phishing campaigns. It contains numerous embedded links, many pointing to disposable domains, which are likely used to redirect users to malicious sites or download further payloads. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://f-kcc.jp/user_data/userfiles/files/lerasaduwaserinorabap.pdf In PDF document text
    • http://at2apigroup3.com/contents/files/wexuli.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/kosazun.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/38506734351.pdfIn PDF document text
    • http://sb-78.ru/files/file/95480417501.pdfIn PDF document text
    • http://uralteplostroy.ru/content/file/91376320876.pdfIn PDF document text
    • https://begili.com/uploads/image/files/kiwiturozoxegukozatax.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/24866862340.pdfIn PDF document text
    • http://levakov132.ru/userfiles/file/42641590997.pdfIn PDF document text
    • http://sporteambiente.it/ckfinder/userfiles/files/45111523944.pdfIn PDF document text
    • http://nexxstep.nl/userfiles/file/rafitabefugufegepenowozeg.pdfIn PDF document text
    • https://beamstraffic.com/amb/userfiles/file/27531132540.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/70442252951.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/ruwojiz.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/161377c17af159---medonefobedugen.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/96oo8kj0cu7f4tkf85712jq55s/97140246308.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/zakepezuvatinekan.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/46231682185.pdfIn PDF document text
    • http://chapelguild.com/images/usr/tokudamukatepesamizegifex.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/10278646790.pdfIn PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/vikebapamunofusagano.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/bibododok.pdfIn PDF document text
    • http://seattledesis.com/fckeditor/file/powivotu.pdfIn PDF document text
    • http://makairways.in/home/makairways2017/public_html/dowalumniusa/ckfinder/userfiles/files/52183581705.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=android+phone+benchmark+comparisonPDF 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_off0000b202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB202 10848 bytes
SHA-256: ca89317b430a091ea57b52d1d664dae18a4ff2650c4967fe7512e92d933e1b74
font_01_sfnt_off0000ca9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e2ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2AE 14300 bytes
SHA-256: 0fe020040ada78af94d741504d078430952533354beda1565f634bf69390b28b