Malicious PDF — malware analysis report

Static analysis result for SHA-256 61f2d6b5f4f55296…

MALICIOUS

PDF

79.7 KB Created: 2021-09-07 02:08:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 013d3f3263b0cdd9a94612aa2041a918 SHA-1: b530d7878ea2f862879ebe101d264a5e6974a6e3 SHA-256: 61f2d6b5f4f55296a4aeed291776114c5c06804f02cd5319d15c650d2a9efc73
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate an attempt to exploit users through deceptive links, likely leading to further malware downloads or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://cructi.ru/uplcv?utm_term=case+files+surgery+5th+edition+pdf+download PDF link annotation
    • https://www.aicsmindia.org/ckfinder/userfiles/files/3534902339.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/7b150e8d5f37c36f461682301dc8ccc3/zozonukenowefipinutis.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/4901976717.pdfIn PDF document text
    • http://dbhsreunion.com/clients/21010/File/xazoz.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5518305e3---94305365944.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202108161843154619.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/fe0d394b4da59f7f777d2ec6c87cb5df/3116400531.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160987badad3e4---subefiku.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/35969712820.pdfIn PDF document text
    • https://songhongresort.com/img/files/72963035048.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc3859b0f9---kutomot.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/naravop.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/3489599731.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/midafagakejokovaz.pdfIn PDF document text
    • http://transfertrolley.cn/d/files/24924823891.pdfIn PDF document text
    • http://zubrcup.by/files/files/1795264453.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/tetimodejeniramofod.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/dolemisikenem.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/33196451137.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/gfsjjobpd518blrdcm37tt0j24/32114205484.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c2e6795900a---gowijevomo.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/dufimazujufalosok.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/76318678025.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_off0000d19e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD19E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B5 11240 bytes
SHA-256: 6cef6c636e876ce52f22bceadd65adebb2324d388b2602b0ad0f4941d327156a
font_02_sfnt_off000103e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E6 17368 bytes
SHA-256: 71de7122ec5b3be2229941c9cab8991339b63d23c39ac16c448ecd4a8d39db40