Malicious PDF — malware analysis report

Static analysis result for SHA-256 8388c0f7f4675196…

MALICIOUS

PDF

76.1 KB Created: 2021-09-28 01:27:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d2a637ad21c46da2b3845b22731943b1 SHA-1: 0d3371e8919b1ba9f6b79f1e3936302d96a388ce SHA-256: 8388c0f7f46751961b23e165f38588de374c5591b18a53026d07d86cf8ce191f
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs and link farm indicators suggest the primary purpose is to redirect users to malicious websites, potentially for phishing or malware distribution. The document body was unreadable, but the heuristics strongly indicate a malicious link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://chcial.ru/uplcv?utm_term=android+biometric+authentication
    • https://hazeloyun.com/calisma2/files/uploads/3749160071.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148e70165c0a---bobasuna.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613dc135ed18d---lemuk.pdf
    • https://clubsecurite.fr/webroot/upload/files/79978699251.pdf
    • http://foto-recepty.sk/images/fotky/nimamokosudidiwo.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/c2fd408c0a80e33b2bc56ab85df147a3/xutedufiwisexino.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac4e72615e---5372123155.pdf
    • http://studioaba.net/userfiles/files/dawusevesinupodexa.pdf
    • http://innotack.com/userfiles/file/55406853803.pdf
    • http://mibenjamin.com/userfiles/file/sokuteta.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/e87f797272fd1231ad2efdc4f37f4fbf/95810631094.pdf
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/63196470172.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614b7b49d942f---82357055515.pdf
    • https://lalicorne-hotel.com/userfiles/file/55687065836.pdf
    • https://blueparadise.pl/userfiles/file/78616904947.pdf
    • https://onsale.social-push.cc/data/fckeditor/files/15693606490.pdf
    • http://cargologicru.com/sadm_files/jokovurupulufepumaditipox.pdf
    • https://alaskaproauto.net/nbloom/fckuploads/file/33330590633.pdf
    • http://sksound.com/userfiles/file/femazufeg.pdf
    • https://otterdisplay.com/userfiles/file/14539531645.pdf
    • http://audiohrestomatiya.ru/content/file/64080140302.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613648363150f---rudiwox.pdf
    • http://mprime.net/ckfinder/userfiles/files/90620551407.pdf
    • https://destockbaby.com/ckfinder/userfiles/files/kofiparevukirudoz.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c06b.bin
c0e85c06941e29cfb995d0df9c0f816328046e9489cf467b9bb818cf327f92b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xC06B 19404 bytes
font_01_sfnt_off0000f2a6.bin
b226ef2768a8ac1725b233830ee0e165666aba4a8a04855ffaef05b227eac4a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A6 10644 bytes
font_02_sfnt_off00010acc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ACC 16792 bytes