Malicious PDF — malware analysis report

Static analysis result for SHA-256 371d376e707152c8…

MALICIOUS

PDF

83.6 KB Created: 2021-09-16 18:43:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ffb8b98b4217f093ceff121afed63c90 SHA-1: a6555634d68828a37f70c098f7929b5f4d06a183 SHA-256: 371d376e707152c8f807ec81b5178cba2a1810fe85502382198020c96a53f7e9
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to host malicious content or phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple compromised CMS upload links and link farms on disposable hosting points towards an attempt to distribute further payloads or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408ecb49da1---puregevalo.pdf In PDF document text
    • https://birotex.rs/images/files/76314126687.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc1769bfd7---jigozujo.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/refavosodozuwi.pdfIn PDF document text
    • https://macroedunet.com/userfiles/file/66615836834.pdfIn PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/setotisegi.pdfIn PDF document text
    • https://bilegt.mn/userfiles/files/xevug.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents/files/matarobugudikiki.pdfIn PDF document text
    • http://aqcorth.specialty-match.com/upload/files/42077719792.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/zanisasawonak.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/77045968452.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316dca4b268---63697625984.pdfIn PDF document text
    • http://elitacasa.it/images/file/lowexasavadakeneporopile.pdfIn PDF document text
    • https://mclandpin.com/calisma2/files/uploads/92742356080.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/lumojugamenufevumobu.pdfIn PDF document text
    • http://yizhu580.com/ckfinder/userfiles/files/63784731809.pdfIn PDF document text
    • http://baheth24cars.com/ckfinder/userfiles/files/97947387314.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/narijilediletuwobijibexa.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/gefar.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/3d7626cdf125589d0aab137906829da7/85730317007.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/kaduguledosupokuvidepon.pdfIn PDF document text
    • http://onroerendgoedindex.nl/images/uploads/8502787942.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=draining+the+swamp+the+nesara+story+pdfPDF 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_off0000e0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A8 17792 bytes
SHA-256: d86f87e736d2766224ce6b3d263696dbfea7aff614e2477a40dd0a75e010e0cd
font_01_sfnt_off00010f1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F1E 11100 bytes
SHA-256: cefdcabd8ae1a2db464d35b66e475ac2d1eea63b46b14c3d2685583ae85a98d6
font_02_sfnt_off000128ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1