Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b90045af4f89c00…

MALICIOUS

PDF

74.8 KB Created: 2021-09-19 02:48:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fb630b28a37e6986eb7563f7089db92a SHA-1: 5a2b839f642718f6bcbc1b31a49a93e41c09b4a4 SHA-256: 7b90045af4f89c006c43c0beabafa7a01ae119f99b9df28855b46bee05df4579
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which are associated with link farms and potentially compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms the nature of the URLs as a deceptive tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://laborke.ru/uplcv?utm_term=top+10+status+maker+app PDF link annotation
    • http://axiomestates.com/userfiles/file/17223014337.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/59664034018.pdfIn PDF document text
    • https://kmkmekanik.com/upload/ckfinder/files/54195610442.pdfIn PDF document text
    • https://38e5bbdfe8be.gdziezjesc.info/userfiles/file/gabokegafisebuwow.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/midofefixam.pdfIn PDF document text
    • http://thebankcardservice.com/uploads/files/dunabatajoroxom.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/81193937260.pdfIn PDF document text
    • http://hujiangsy.com/upload/files/vorasitexorerijate.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613404f06880d---63114571815.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/bogilezojer.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/97347950504.pdfIn PDF document text
    • http://unityproductions.com/upload/files/lifezej.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/d0fda5d582086adbeb98d99988fb90ef/44619431008.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423eaac9514---nuruwegugufibaba.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/89107092794.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/dad23228f48437b50e9b321ba861737f/sederinigajuledoz.pdfIn PDF document text
    • https://codecs.ro/images/file/34156619864.pdfIn PDF document text
    • http://jiji.pgo.tw/pic/uploads/files/47401090259.pdfIn PDF document text
    • http://hpcad.pl/Upload/file/93084242583.pdfIn PDF document text
    • http://123flower.doweb.kr/upload/files/39105427753.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/nibovig.pdfIn PDF document text
    • http://mayphatdienngocquang.com/media/ftp/file/gatem.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/91250877604.pdfIn PDF document text
    • 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_off0000c537.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC537 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD49 16020 bytes
SHA-256: f2934b55422ec044adf4828bae3a9e21d52d6a0ac7ad379f735e0357d58e3bcc
font_02_sfnt_off00010620.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10620 10500 bytes
SHA-256: 0fedbf43fd9ec0a894eeeab80daa38cba5d5762e87b0590b0aa045cfc8ae0e08