Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5676bfca9e25a25…

MALICIOUS

PDF

72.0 KB Created: 2021-09-08 22:56:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4510bb3e65838fbb5ab416ed24ec6c1d SHA-1: 6c3316afe245d9f26f7cbac1d1e162a02bf9c70d SHA-256: e5676bfca9e25a255fa2d20fab18fe7ff0ba031855675cff8c628e28af54bc88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many hosted on compromised WordPress sites, forming a link farm. While no scripts were directly extracted, the presence of embedded URLs and the nature of the link farm suggest an intent to redirect users to malicious or phishing content, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1613139a537d03---64525709035.pdf
    • http://www.39koratmachinery.com/file_upload/files/47138234125.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/1a4b82338c084c3e76d4385ef7627029/64730189454.pdf
    • https://bistakalikotenetwork.com/userfiles/file/jubovoxiweta.pdf
    • https://rolcsi-bau.hu/userfiles/files/45807352498.pdf
    • http://predit.ru/admin/ckfinder/userfiles/files/15252980769.pdf
    • https://salonrewards.ca/images/file/35524422842.pdf
    • http://musthighschool.mn/ckfinder/userfiles/files/76914018845.pdf
    • http://phupmirpol.pl/userfiles/file/63459324116.pdf
    • https://valstybestarnyba.com/upckfinder/files/50686986685.pdf
    • https://jordanadams.com/ckfinder/userfiles/files/soxuse.pdf
    • https://terminarz.online/kosmetyczka/krakow/files/fubasesebejalolaloraza.pdf
    • http://a-b-i-s.net/layout/bilder/file/75444856524.pdf
    • https://centrorevisionimonregalese.it/file/tavamezejupopakefizoxif.pdf
    • http://clean-ecology.com/Upload/files/85798817173.pdf
    • https://masukpt1.com/contents/files/48329402605.pdf
    • http://potya.com/sovox.pdf
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/tabitusugifixojimelejuro.pdf
    • https://dgssu.com/upfolder/e/files/20210906180502.pdf
    • http://indemo.pl/Image/files/55950581630.pdf
    • http://asea-admin.com/_userfiles/file/20210908080548.pdf
    • http://shopgraeagle.com/ckeditor/uploads/files/jabodi.pdf
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/f52fb07b07d4006389e0833520789f8a/gugajutovoxuf.pdf
    • http://vagtteam.com/userfiles/Files/vosefawaxalamiwisekof.pdf
    • http://3e3i.com/UserFiles/file///41249753577.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=android+sketch+paper
    • 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_off0000b7a1.bin
bb9558d16b93201fa47032b5bb5d26f9db4c6947b8ec22b884f125d75b6e6634
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7A1 16488 bytes
font_01_sfnt_off0000e23d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE23D 16792 bytes
font_02_sfnt_off0000fa54.bin
61dac84885a82135eae262b8791ddaf693f776c94493316ac3dcfe867989aba5
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA54 10640 bytes