Malicious PDF — malware analysis report

Static analysis result for SHA-256 852f8d8e044f685a…

MALICIOUS

PDF

71.7 KB Created: 2021-08-29 18:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0e857f1b8752429373d2023b763a3c8 SHA-1: 49fc259d28f48c621d2b2aca1c4cdb97e3789bfa SHA-256: 852f8d8e044f685af8249415852946002a30ed1c9a4ddaeb6a2efdc22643bb46
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to potentially compromised WordPress sites or disposable hosting. The primary purpose appears to be directing users to external, untrusted resources, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160969cae04759---nazesirovapoligugavujinu.pdf
    • http://sys-svinding.dk/userfiles/file/29744832977.pdf
    • http://elitaliaweb.it/upload/file/tibedapinav.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/f89e526bf121f4c0f3e555c71b91ba83/kidipujuzapisa.pdf
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/e3b01b966272c1753309448e0dfe89a5/71464477299.pdf
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/91879270175.pdf
    • https://maintogelonline.bet/contents/files/kujorizefiw.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/8a0snhbifk0k52a3tju1getqe9/fepivegepegezarufibef.pdf
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/vimudibigedibobofibubina.pdf
    • http://www.recko.ru/ckfinder/userfiles/files/77222371225.pdf
    • http://mppscstudy.com/admin/usercontent/file/zuzitamipevuwipokak.pdf
    • https://alamansyria.com/userfiles/file/22806601307.pdf
    • http://profesniprukaz.cz/ckfinder/userfiles/files/69230417711.pdf
    • http://firmykominkowe.pl/Obrazki/edytor/file/wijoxejusotufepedijum.pdf
    • http://romanakladatelstvi.cz/userfiles/file/19198456181.pdf
    • http://fujiya-la.com/uploads/files/64218531296.pdf
    • http://ledseoul.com/userData/board/file/gidakev.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901e9dbbc47---19635752712.pdf
    • http://globalbando.com/DATA/upload/files/202107090005511161.pdf
    • https://alariel.be/userfiles/file/90313753377.pdf
    • https://twfern.org/upload/ckfinder_temp/files/20210625015633.pdf
    • https://essuances.com/ckfinder/userfiles/files/gusozipaf.pdf
    • http://1yunnan.com/ckfinder/userfiles/files/9732138646.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=south+tech+middle+school
    • 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_off0000bb49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBB49 16792 bytes
font_01_sfnt_off0000d35b.bin
02a1ac2c812bbae99ffbc123e1ef07925b9d42796708bcd7330610ef58ec40d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD35B 15136 bytes
font_02_sfnt_off0000f8f0.bin
d935e4186ab461449079181f35520e5860a287714822aee0af0c068ac4d7c857
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F0 10444 bytes