Malicious PDF — malware analysis report

Static analysis result for SHA-256 e51337262511179a…

MALICIOUS

PDF

86.9 KB Created: 2021-09-12 01:15:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5fefa45a657c76ee25b90a2efbd6cbea SHA-1: 98abb244a363813ec13cb5003b66efbc2c5f50de SHA-256: e51337262511179a432e84b1a144f149bf602874fba34e83196f7ec7e18f16d0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were extracted, the structure and URL patterns are indicative of a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/1a50230f4fe41e5681c824e1336f7237/82547097259.pdf In PDF document text
    • https://noticky.net/akce/fotky/file/ramorizijerow.pdfIn PDF document text
    • http://inica.org/files/file///75423736966.pdfIn PDF document text
    • http://pk.mo/userfiles/file/mikajelof.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c2b3561ac6---rufilukafiviboxibifiletam.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/maxodoripiwovukirimuf.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131556236709---17790324391.pdfIn PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/siwoxo.pdfIn PDF document text
    • https://specializedfacilitymgt.com/public_html/userfiles/file/38814634483.pdfIn PDF document text
    • http://uslugi-ogrodnicze.pl/pliki/File/kuvukugadodoxogepamizago.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/50435764486.pdfIn PDF document text
    • http://donghotam.com/luutru/files/memowos.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/5788776751.pdfIn PDF document text
    • http://romangruszecki.com/uploaded/file/15869790793.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/91395094664.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/9010a069d3c0aa7451ca4cb68b908ae3/zuxurulexox.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/74033098354.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/levinakulozivad.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613284164f582---45517061683.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/dugonepolu.pdfIn PDF document text
    • https://cakkue.com/contents/files/55797354121.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=non+chinese+mobile+brand+in+indiaPDF 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_off0000ef55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF55 10656 bytes
SHA-256: 83faeb0ff42b2caa3bd4725798058a5e286bfb6539ead65d8eb72365c75872ee
font_01_sfnt_off00010771.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10771 17944 bytes
SHA-256: 07fc7ec1b798f5a1816a10cc79fc9b69a27f635bde3e3d46ee879ed2934e9dbf
font_02_sfnt_off000135dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1