Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98a39f957809b99…

MALICIOUS

PDF

81.4 KB Created: 2021-09-16 02:58:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ed7a596d100d52d0c947fc978a117981 SHA-1: be035fa02fd421321eb95ee29303fd31c1a6846c SHA-256: a98a39f957809b99b0773024778df5e1e409dfeb5e0b9394435daf7c11678645
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or other potentially untrusted domains, indicating a link farm designed to lure users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL distribution are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/abfierdkd6e8biphab7mm4moce/29349763170.pdf In PDF document text
    • http://architettoseneca.com/userfiles/files/wigilikurutitexose.pdfIn PDF document text
    • http://boilerservis.ru/uploads/files/94504282391.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/kumitosirexuxetebanisez.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/19487325806.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/37527604940.pdfIn PDF document text
    • http://trungtamsangloc.vn/uploads/ck_upload/files/maxopages.pdfIn PDF document text
    • http://missteenqueenuk.com/userfiles/file/62515244750.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/lopavamerokiga.pdfIn PDF document text
    • http://campbellelectronics.com/uploads/34313194383.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec30b1bf0d---xenekozegamubuteju.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/salegoj.pdfIn PDF document text
    • http://conelser.hu/fck_uploads/file/nuxisadoragakiji.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/32228118576.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/4533487836.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/sixedaxovox.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/99897597506.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/27ae91d8a72c76e9a13f8274880359b1/mijofexugalerapasibamibin.pdfIn PDF document text
    • https://ofcourselc.com/admin/uploadsfile/dojokezoloxi.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/85442019932.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/95850615044.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/21241539581.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=skyvpn+mod+apk+2020PDF 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_off0000d33c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD33C 20004 bytes
SHA-256: 7e81a58afb468794ed602f0781654f8673eba8e9796fba660c04e79600a30a9b
font_01_sfnt_off000107f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F4 10508 bytes
SHA-256: 84f29153dbfef60560f7d8deeee4613eed4c07a8266aebbf2e178643199c3777
font_02_sfnt_off00011fe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1