Malicious PDF — malware analysis report

Static analysis result for SHA-256 b35ba3d51253b980…

MALICIOUS

PDF

81.7 KB Created: 2021-09-19 11:49:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0dfab0112c85a98a69142e67aeb21dee SHA-1: b510a2f0832571d919a263329a6cc6fe711086b0 SHA-256: b35ba3d51253b9800ce06512590c22248d0c17a4b1654c4aea934da419786ef0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous embedded URLs, many of which are algorithmically generated and hosted on disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://cructi.ru/uplcv?utm_term=inshot+tutorial+for+android PDF link annotation
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/gidapufukunudorufel.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/sakita.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/gexode.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/55730056411.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/kozopavanebuwopun.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/c7c8f2e937b48e791f13e1626e51f38d/76844344070.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/48998919216.pdfIn PDF document text
    • https://krusomying.com/data/file/16231610532.pdfIn PDF document text
    • http://chornakorn-packing.com/ckfinder/userfiles/files/13387129530.pdfIn PDF document text
    • https://www.hkha.com.hk/ckfinder/userfiles/files/71920055628.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/74528713365.pdfIn PDF document text
    • http://ozkayalarlojistik.com/userfiles/file/wamokodirali.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/kuvefisozululawif.pdfIn PDF document text
    • http://dioblina.eu/userfiles/file/4664116775.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/92586941186.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/raselejitevawijulike.pdfIn PDF document text
    • https://idosekotthonaveresegyhaz.hu/files/files/60451477516.pdfIn PDF document text
    • http://dfwsedan.com/nbloom/fckuploads/file/juvikunenufetivipip.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161446c0684211---wijexod.pdfIn PDF document text
    • http://mobitransjogja.com/files/88429594210.pdfIn PDF document text
    • http://marmaraisg.com/images_upload/files/vugopuzoxikakotomomet.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/85333264980.pdfIn PDF document text
    • http://bowlingkillers.com/imgdb/files/23919027073.pdfIn PDF document text
    • 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_off0000dd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD32 17320 bytes
SHA-256: 8ddceeec09f37825c87ebcacdb314f78323d1f929f03ba771f08ead9ff12c9b7
font_01_sfnt_off0001099b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1099B 10368 bytes
SHA-256: 7adee499c23b84b34bd0b99c3449332c3487b93f0bbf5abec097d9de502dd4e4
font_02_sfnt_off000120e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1