Malicious PDF — malware analysis report

Static analysis result for SHA-256 260966ec8cc65352…

MALICIOUS

PDF

83.5 KB Created: 2021-09-15 15:01:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4b50526cc7e0a4a7ea5ef5d372d4828c SHA-1: beb49b4c00cb40471c166cabb24f76e88ac75b68 SHA-256: 260966ec8cc653524284bd7f5d168d108c6230f9640ef918f89e403d8511c5e0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The presence of numerous external URIs and link farm heuristics confirms the attack pattern.

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://machnhaduong.com/images/uploads/files/tibelupafukokisovoxokepup.pdf In PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/h6v9cftf4lum71a3rhre17d924/fejewamigowiwevinivajefun.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea4a22a91f---39994020260.pdfIn PDF document text
    • https://nycsmindia.org/ckfinder/userfiles/files/difekiruwato.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/48373943590.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/34148076731.pdfIn PDF document text
    • http://mail-business.ru/uploads/file/pawur.pdfIn PDF document text
    • http://chanakol.com/ckfinder/userfiles/files/49405240269.pdfIn PDF document text
    • http://ricettebiagi.it/uploads/assets/file/gepili.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/79638962201.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/bexofubas.pdfIn PDF document text
    • http://abwcockeysville.com/uploads/files/269789802.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136cf9b64a78---xuziderazenu.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/tukukene.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/dojopoxupetebazujejajizes.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/renegepo.pdfIn PDF document text
    • https://bushregenerators.info/userfiles/files/61792882037.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/39888996283.pdfIn PDF document text
    • https://hiroyoung.com/data/files/lurarazugeroge.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/bobakejorezigalibaxan.pdfIn PDF document text
    • https://alistairmills.com/ckfinder/userfiles/files/4126408206.pdfIn PDF document text
    • http://alarm.pl/userfiles/file/16951337511.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210913161341.pdfIn PDF document text
    • https://www.syria-report.com/sites/all/libraries/ckfinder/userfiles/files/jetikufedufetekorobakefa.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/kaitu1bjr74k5dokq00l3m2l6v/taketemowupalotuwisosasa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=android+system+cleanupPDF 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_off0000dec0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC0 18660 bytes
SHA-256: df87b76df144cd04f54240e8f4463a3e733f4aa85e0ba651ed16e93eaa1776c5
font_01_sfnt_off00010ee5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE5 10872 bytes
SHA-256: fcb54601e60e368de68ff2de6a23cc37dd4a339f8ae9abca996e09bda3ec0dbf
font_02_sfnt_off00012811.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12811 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1