Malicious PDF — malware analysis report

Static analysis result for SHA-256 510813b914892db3…

MALICIOUS

PDF

85.0 KB Created: 2021-09-13 05:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9da4dbb4eeb175b28e243bc5042c223b SHA-1: 491ed3dbc686ad7eed1a0ab05a2637d5f962cb3a SHA-256: 510813b914892db3544a7e7f110193d0b0553bf23810416ee1f524c11616121c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of a link farm pointing to numerous distinct hosts, some hosted on compromised CMS uploads, suggests an attempt to distribute malicious content or phish users. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://rumusjitu.com/contents/files/75209830151.pdf In PDF document text
    • http://mottaing.eu/userfiles/files/jugawije.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/81994951273.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/puboze.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/97368325712.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb177adea1---41995260859.pdfIn PDF document text
    • http://studioingtassinari.eu/userfiles/files/soxefagozuxevugonaveziwe.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/peput.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf0790e5a9---nekamuzetosipax.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369ae1a9334---64491613078.pdfIn PDF document text
    • https://indoshaolinkungfusociety.com/ckfinder/userfiles/files/nurokijofu.pdfIn PDF document text
    • http://www.trisad.kz/ckfinder/userfiles/files/53860173611.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613805d34debc---55732269927.pdfIn PDF document text
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/pimolowomisagokukasovu.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/80410389606.pdfIn PDF document text
    • http://deshdunya.com/blogimage/file/telujoseduf.pdfIn PDF document text
    • https://phu-komplex.pl/pliki/file/loxamiseka.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/japivibirilawisatalolo.pdfIn PDF document text
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/bikojub.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/fomukuwu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=wlan+hacken+mit+androidPDF 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_off0000e6c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C3 18524 bytes
SHA-256: 13ed74a11cc3dc68f3cf3dff5aaaea687f9dde987f03d4d31d47f0c78b4e12d8
font_01_sfnt_off00011566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11566 10552 bytes
SHA-256: d7687cdac7f24807dbc382560631c7836b22d664035543cf5c98765b8de4da73
font_02_sfnt_off00012d40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1