Malicious PDF — malware analysis report

Static analysis result for SHA-256 813965ab2d77cc76…

MALICIOUS

PDF

86.9 KB Created: 2021-09-13 12:34:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2a7d6305631e1be19fdf0f557e11fec1 SHA-1: b7c9a07d68961b4b37ce68b359791a8a25645179 SHA-256: 813965ab2d77cc764183735d076c369b9167cdf6933138437a96612f115bf14b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple embedded links, with one specifically identified as a random URL pointing to another PDF file. The 'SE_CALLBACK_LURE' heuristic suggests a phishing or tech-support scam context. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://emilline.dk/ckfinder/userfiles/files/rabonofipumuleve.pdf In PDF document text
    • http://filippodelvita.com/demo/userfiles/file/momedininen.pdfIn PDF document text
    • http://mosme.org/uploadfile/files/63997637171.pdfIn PDF document text
    • https://castel.ro/userfiles/file/48662045474.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/ripap.pdfIn PDF document text
    • http://sportingclubalbinia.eu/userfiles/files/60072123096.pdfIn PDF document text
    • http://drigungkagyurinchenpalbarling.org/upload/userfiles/files/gadekojodigivezetat.pdfIn PDF document text
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/mesasamuzasulumemawovem.pdfIn PDF document text
    • https://www.parquesanalbertohurtado.cl/ckfinder/userfiles/files/vepamubosogajigofugaxilus.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210902_D3584B2CC5534241.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090723533555.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/56787534096.pdfIn PDF document text
    • https://aadharshilaschool.org/userfiles/file/wunuxedupidafaxejegun.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613526e80411b---bagusigegatimimaf.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/tofatefedanojudetatubovu.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/27652588955.pdfIn PDF document text
    • http://csc028.com/userfiles/file/20210913164558_si01ji.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161397a42e4900---wumes.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/21642729506.pdfIn PDF document text
    • http://maksimetall.ru/files/3059822194.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/15659392771.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/rijogajokabidumajebabu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=items+to+make+in+minecraftPDF 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_off0000efbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D3 10492 bytes
SHA-256: d9da65a69daf7754d49ad7928829c9ca421e1e180b3bb57394016f024150e716
font_02_sfnt_off00011fb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB0 17836 bytes
SHA-256: db35c15d3ae1a0c693e3812eeb77372b4204bb346a9c573f167e5a00b9a7c776