Malicious PDF — malware analysis report

Static analysis result for SHA-256 d63ea4286c31f89c…

MALICIOUS

PDF

124.1 KB Created: 2021-09-07 07:20:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 408e8b3ad5a5e50b6c66fc2656d6581f SHA-1: cee12b92cb0423191dffe4661bb06a36df3ab042 SHA-256: d63ea4286c31f89c99eccf31ba3bd4436b57c45f47b768eb4620f59a64328315
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identify it as a link farm hosted on compromised CMS upload storage and disposable hosting, with numerous embedded URLs. The primary purpose appears to be redirecting users to potentially malicious sites, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://www.sesc-am.com.br/Selecao/ckfinder/files/39863409242.pdf In PDF document text
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/g02qq8ikt7aodcsakvmurarc7n/goberasasatilawor.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/b8dc3fab4c09e0cf1b3229d7a9f466f2/fefibasodifakivem.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094370a97a73---11859534222.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/93215227839.pdfIn PDF document text
    • https://divinenine.net/userfiles/file/potox.pdfIn PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/87310231209.pdfIn PDF document text
    • https://pingthye.com/userfiles/files/nujupirefewero.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/papurazimigoxupit.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/donudufazugevarapulikasos.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/jotamudeperugigaz.pdfIn PDF document text
    • http://www.hon-ro.hu/userfiles/files/33467812678.pdfIn PDF document text
    • http://vucert.vn/uploads/files/pilererefetup.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/walavamalezofata.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/36e01ed85fbc5c034722e3e56638d1ac/43354701400.pdfIn PDF document text
    • http://mdtrend.hu/files/file/79501393989.pdfIn PDF document text
    • https://ispartaprefabrik.com/ckfinder/upload/files/kuruwozupibunewipevaw.pdfIn PDF document text
    • http://jinohair.com/upload/files/75252664372.pdfIn PDF document text
    • https://mayurherbal.com/userfiles/file/28690530442.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/78763041162.pdfIn PDF document text
    • https://kristinanamaste.eu/files/65199687079.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=customer+relationship+management+articles+2018+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_off00017b81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B81 19528 bytes
SHA-256: 1613a0e7fa591fd63bb4058decef03dc30a50cc26497da402df5e763f497e6c9
font_01_sfnt_off0001ae96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AE96 11700 bytes
SHA-256: bbbfabd4feec142c1bddf37d334959e0b7f33d3b791ff0289b79cf0c9fdf664e
font_02_sfnt_off0001ca2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CA2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1