Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27119af78a93107…

MALICIOUS

PDF

87.3 KB Created: 2021-06-28 13:48:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7e8ad940c10e5ad9b4986ade6c04c830 SHA-1: 8bb34b07b5e458997dbfb525350f08c58e72daa4 SHA-256: a27119af78a93107d78077b070091b976a34cb1ed92c6d772d8b32dc937f2fef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it's a link farm pointing to compromised websites. The PDF contains numerous external URIs, suggesting it's designed to redirect users to potentially malicious content. While no scripts were explicitly extracted, the nature of the link farm and the detection as a phishing trojan points towards an attempt to deliver a second-stage payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://szentimresiklos.hu/upload/file/35558711193.pdf
    • https://beautyreviveshop.com/newerac2c/userfiles/file/82979779228.pdf
    • http://auksozvynas.lt/userfiles/file/turuse.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607e96f59b049---19319474296.pdf
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/d27bdd170c98233259bc8911d9079d9f/10216040004.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607726442965f---56180510861.pdf
    • http://cnpair.com/userfiles/file/vowiwojikorudifaxokakex.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/1t3j6t4rvh3o0qfcuj7n9mslk7/wogapemopugobamobemimime.pdf
    • https://bleikss.com/userfiles/file/6727418356.pdf
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/qg3d0jbn1nt2070c7cm0r004bm/zaxoraf.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/020513bcab0853ed58b0e1169b74738e/nabuve.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3cb32822cb---wolejurepowugupemeges.pdf
    • http://cngwalk.com/fckeditor/userfiles/image/xelitibenipalotumetiw.pdf
    • http://uptownchantilly.com/uploads/files/5852477759.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ad454be0eccf13fa9ca534673b373c37/25438523101.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/ul38j6jd7t4mr8phppsvhe4fh3/33488775458.pdf
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/sceq0v95pnfup7v8e9rvv3jgpr/69705173861.pdf
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/d7ab1efb9e7d31af67afe83eefeb29ec/39593553042.pdf
    • https://careersourceokaloosawalton.com/files/public/46486600848.pdf
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/aml1krc6h3rjqqdtlg9qee313a/jesetadalem.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607a79b918980---46779154940.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a710f01a1ef---97165546274.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/b1faff4b4d2e21d1706c5cb7464a5db7/87961520661.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160866f785ae16---xonisuzupobuvewukos.pdf
    • http://budohurtsa.pl/userfiles/file/xefinobologurubobuxupe.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=translate+excel+to+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_off0000f115.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF115 16792 bytes
font_01_sfnt_off0001092c.bin
e3aa2a01333d10b474532995c99a272a9483dd6eac4479606ae3364ce9456e43
pdf-font-stream PDF embedded font (sfnt) at offset 0x1092C 10588 bytes
font_02_sfnt_off0001217f.bin
f34c5e92112bb4ab9b403f3aa8b632b6944a18c165c5d19694580c42c37f3aa1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1217F 18636 bytes