Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ef7a43550240101…

MALICIOUS

PDF

79.0 KB Created: 2021-09-08 15:27:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 35d135355317066dc2e0aba19e27538e SHA-1: 11a9ac295257460df11ec3fd887f51ab126bd4c6 SHA-256: 2ef7a435502401013dbe52035c174adc8916916a417d1906aa4cebcd018ab7e4
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs likely lead to further stages of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://crewmak.ru/uplcv?utm_term=letter+attachment+pdf PDF link annotation
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/89195317065.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/38443979020.pdfIn PDF document text
    • http://e-photo.lv/ckfinder/userfiles/files/josasejoge.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/49124207695.pdfIn PDF document text
    • http://campbellelectronics.com/uploads/6426588147.pdfIn PDF document text
    • http://ledlight-lamp.com/mingyi/images/userfiles/file/gemoxaj.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/ue4fog2jgvke4c23ljto2llrmu/gefumujanubazoguvonizo.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210904022810_3v3cg5.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131028c79e8f---94439020144.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/04d569ae5beb54f788cddfb4b12f0eec/fokugemigalegojuvewikag.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/bakavipobopujadodaxip.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/51553628541.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/51993697365.pdfIn PDF document text
    • http://sdes.in/uploads/40663114334.pdfIn PDF document text
    • http://okvin.org/userfiles/file/84562324489.pdfIn PDF document text
    • http://primaneighbors.com/userimages/74957360503.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/relesomojadamo.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/tovapuxoneger.pdfIn PDF document text
    • https://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/vulunititim.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/85219021818.pdfIn PDF document text
    • http://hyundaidongdo3s.com/images/files/86503705806.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/96885611466.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/dajiwilafebunivegata.pdfIn PDF document text
    • https://heureka-cz.eu/files/xowizofuxaxiwenefafa.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/68554250821.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_off0000d230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD230 10416 bytes
SHA-256: 6119cd01add37ae4b2afab23c952f5792cdbc99fdd1f1349f4ff302de8f47b4e
font_01_sfnt_off0000e993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE993 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000101a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A5 17568 bytes
SHA-256: 2ba716803b6d40dc9bf00db02edceb5e2869d244f90b5903a09a1c679747c853