Malicious PDF — malware analysis report

Static analysis result for SHA-256 13957c6ca059c81b…

MALICIOUS

PDF

79.9 KB Created: 2021-09-20 15:06:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4d8ada0ba0da7fe3f892208b4729d9bb SHA-1: bbfa2e5490600bbcbcd19062547fd225171fb8e9 SHA-256: 13957c6ca059c81bf94c5fc9c874eedf4c08b16a0b3c670e9711f210c2432b34
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, suggesting a link farm designed to redirect users. The presence of these URLs and the PDF structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://itexpertdog.nwoasis.com/upload/files/tokuwiwalezejupomufa.pdf In PDF document text
    • http://nollve.com/img/editor/image/file/mubovegifesokuzi.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/najumoxomarokatez.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/puwenatarezatatopefev.pdfIn PDF document text
    • https://purefeeling8.com/data/file/44598106515.pdfIn PDF document text
    • https://hgqq.hk/tony/churchofgod/ckfinder/userfiles/files/mojefas.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/bcac1ff240509a4118daa073de6e62ea/45711650538.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/09/file/loxenotagelapixe.pdfIn PDF document text
    • http://sevgineslianaokulu.com/ckfinder/core/connector/php/uploads/files/dojebaligulib.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/kixozawamo.pdfIn PDF document text
    • https://aksusu.com/upload/files/89344752437.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/11264630045.pdfIn PDF document text
    • https://khmernative-rice.com/userfiles/file/75177561451.pdfIn PDF document text
    • http://sun-dr.com/uploads/files/202109200201526974.pdfIn PDF document text
    • http://topmebli.com/content/xuploadimages/file/jatebisivumagefabegon.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1612ece1feb577---gagulamekimosefivize.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021090313571373499.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/doditemomogaboxil.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/4c94234e23fd6606697ae2959d75c000/gafufidinumuwavozu.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/12800400171.pdfIn PDF document text
    • https://ist-lb1.istanajp.com/contents/files/pamibe.pdfIn PDF document text
    • https://refakatci.net/userfiles/file/62578262721.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=empire+of+storms+pdf+downloadPDF link annotation
    • 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_off0000d391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD391 10728 bytes
SHA-256: f02979c59d6e4aa4f930391c5dcc5bc8e1ee147a23775ddd192d3505c0fd38e2
font_01_sfnt_off0000ec34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC34 17696 bytes
SHA-256: a40a6418e5e4e655b753e869a4fd2e01a4ec50f2df5cf0b10973a44c6b2632ca
font_02_sfnt_off00011a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1