Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0739de18f158c2f…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 17:12:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 77aec600b4d70d77a79ded05be478a03 SHA-1: 0aeff6f96eac37e6b4a933726c9e1f008903cea1 SHA-256: b0739de18f158c2f2ff8d68055498279e3a68c1c7149aa8c8cce91ed8b255fa1
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, likely to redirect users to malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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://nevisnews.com/userfiles/9252339822.pdf In PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea71890cb9---vusinaniriwimalafu.pdfIn PDF document text
    • https://carlojans.com/cms/file/46352205383.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/49884688464.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/64172973598.pdfIn PDF document text
    • https://pbpkrosno.com/fckfile/87057798199.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/89529711587.pdfIn PDF document text
    • https://milsagliksen.org/upload/ckfinder/files/sidowenudul.pdfIn PDF document text
    • http://itcck.org/upload/editor/file/84951559170.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/84431722694.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/duvubovalukowolif.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/widomebojo.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/42773627956.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/2273015584.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/iipcmglcrs6jhnkcp1flu7ioq4/pabezuxevuneridubepisa.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/wexisopevozanibi.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/9784547365.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/a06iei04fh2sc02lohd9liq1hu/xosawetadil.pdfIn PDF document text
    • http://bilafafafa.com/shopadmin/upload/files/zaxasu.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/56243099869.pdfIn PDF document text
    • http://gimnazjum-krasiczyn.pl/img/userfiles/file/vekomogimak.pdfIn PDF document text
    • http://kuppersbusch.hu/userfiles/files/47699743338.pdfIn PDF document text
    • http://contelex.it/userfiles/files/83604828011.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=scholastic+book+clubsPDF 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_off0000da43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA43 18628 bytes
SHA-256: 2e67b2a9f27dcfbeda40c522351d5d383318b728a78030b45e6dbb297bb60749
font_01_sfnt_off00010a57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A57 10400 bytes
SHA-256: 249e6847b7bc68412fd65c3f037f5c7aef58cfc9e4f525ee785de3fc1947def1
font_02_sfnt_off00012205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12205 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1