Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ced874918c38e83…

MALICIOUS

PDF

79.2 KB Created: 2021-10-10 18:07:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3e3e1b46fdddcbf80fff9a82ae2e3383 SHA-1: 2fb94ce09ced4e451066674777243d3985f7b168 SHA-256: 8ced874918c38e834eaceaccc71911ce7643da805d59356ffedc1a5ddf62cd64
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO manipulation scheme. While no scripts were extracted, the structure and URL patterns indicate the document's primary purpose is to redirect users to potentially malicious or phishing sites.

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://b2bircruise.travflex.com/bot/ckfinder/uf/files/24678765393.pdf In PDF document text
    • http://homeloanz.net/images/e/file/xalavemimoxikug.pdfIn PDF document text
    • http://sictombbi.fr/ckfinder/userfiles/files/64062001354.pdfIn PDF document text
    • https://karlschool.org/uploads/files/202109111553027324.pdfIn PDF document text
    • http://thuaphatlailongthanh.com/upload/contentFile/minhchau/file/89863931061.pdfIn PDF document text
    • http://393citizen.com/upload/files/18167381686.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147c99d60834---86963007821.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/kaloranemozurorurame.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/dedovovuwenod.pdfIn PDF document text
    • http://epicridesnepal.com/files/28287148851.pdfIn PDF document text
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/66974799910.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/45607917578.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/20999120670.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/lutavukoferowoxukinomu.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1f3f9457a---xozufonaxovameli.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/45046558469.pdfIn PDF document text
    • http://yanartextil.com/firma/files/tofuzugatebubevugotosune.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/46c5a34db99119d39170ca8d79fa3886/sekejex.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16145860295e09---55469371023.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/pnncvhn4tkd4epub2gkqf1euiq/woloxelu.pdfIn PDF document text
    • http://xn--80aer5aza.xn----htbdepbihnfb8cyg.xn--p1ai/ckfinder/userfiles/files/zowukizawiseroderobomazot.pdfIn PDF document text
    • http://qdcmd.com/data/files/fomotewaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=thomas+calculus+solutions+11th+editionPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/82869342477.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_off0000d259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD259 10648 bytes
SHA-256: c37ce3f4496590dbc4198f0a198a192e0915a652bd6d938b245116dce6b0aa35
font_01_sfnt_off0000ea9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9B 17160 bytes
SHA-256: 59806bbf195da6b95b725b2cd4f021a763072eec34419d0eb6a9a8ab079f6613
font_02_sfnt_off000116bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1