Malicious PDF — malware analysis report

Static analysis result for SHA-256 531a3c50b8330d1f…

MALICIOUS

PDF

74.6 KB Created: 2021-09-13 23:12:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e4727e2e37b07d7dddaea2c2395b2af2 SHA-1: 21ddc1ff15bf01ef4204eb05341da51850567cbb SHA-256: 531a3c50b8330d1f68adad639f371ad9700468e9aefcd4380621c7e5454ecfdf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and heuristics point towards it being used as a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ketchas.ru/uplcv?utm_term=dr+who+battlefield PDF link annotation
    • http://encino.ilovepokebar.com/uploads/files/84651248530.pdfIn PDF document text
    • http://ilksolar.com/Images/Media/files/sojef.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332c8cd33dd---78643841937.pdfIn PDF document text
    • http://mudrberanova.cz/userfiles/file/82602785691.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/mateganazas.pdfIn PDF document text
    • http://ttlh.vn/storage/ckfinder/files/tevugogonoj.pdfIn PDF document text
    • http://ferramentabelleggia.it/public/file/92632976284.pdfIn PDF document text
    • http://studioarchoggianiepartners.it/userfiles/files/7581807684.pdfIn PDF document text
    • http://www.gulbaharsigorta.com/contentData/file/zilufuvunididuwew.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/52494132226.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/reladapalekuvixade.pdfIn PDF document text
    • http://ipceurope.com/assets/file/93161442999.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/wuzukesejidukusufokajez.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613043fc571c7---85358688281.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/39539464654.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8822cdf91---61057964833.pdfIn PDF document text
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/62542554702.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/xisasuparubulevi.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/28901961965.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/junorivuvisinew.pdfIn PDF document text
    • http://niktid.ru/userfiles/file/latoturapuguwekowalikug.pdfIn PDF document text
    • http://edmo-cars.nl/images/file/jabigakezasejefimovetejiv.pdfIn PDF document text
    • http://thekreativecompany.com/uploaded_files/userfiles/files/1541945051.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/13989345780.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_off0000c1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1F1 10404 bytes
SHA-256: ee813e525cb83e6920ff06f6dc976cccd901b89d6dfd0b25269c5912013efe2a
font_01_sfnt_off0000d9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A0 16784 bytes
SHA-256: 992b8d4f21afb66ca0b70bd8dddcab63a23a17286e1d6eee8bc78c27e3a63b19
font_02_sfnt_off0001052d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1