Malicious PDF — malware analysis report

Static analysis result for SHA-256 25016e1c64b23f2e…

MALICIOUS

PDF

84.1 KB Created: 2021-05-22 11:17:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 98c5a3527683e85d8878676952d3b96b SHA-1: 76754754394d10b825009e8384425af7839f0197 SHA-256: 25016e1c64b23f2ef0d127814ba4aa522bfc75823d54ef9e3ff63d7d559bf44b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://leonvi.ru/strik?utm_term=jsc+scholarship+result+2018+dhaka+board+pdf+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4462066/normal_60450a195b08c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384308/normal_606593659398c.pdfIn PDF document text
    • https://letazofuwukuge.weebly.com/uploads/1/3/4/8/134869061/lufotil.pdfIn PDF document text
    • https://fotaluxig.weebly.com/uploads/1/3/5/9/135973299/5c7f09eff02e4.pdfIn PDF document text
    • https://jukafubu.weebly.com/uploads/1/3/0/8/130874261/1568233.pdfIn PDF document text
    • https://rafitiwaxaxeb.weebly.com/uploads/1/3/4/9/134903343/nakoba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415304/normal_60437cd37a508.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443799/normal_60661b690b4a1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379369/normal_5fd687759316b.pdfIn PDF document text
    • https://fixoxotogixas.weebly.com/uploads/1/3/4/3/134374926/nitedurefukid_fewixezewaxivoj_duririm.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418584/normal_60090db062636.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380393/normal_600c0a529c23c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448124/normal_604d0a36d3f41.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/f40690de-4f70-4279-8096-dd03dbb19bcf/how_did_spain_colonize_texas.pdfIn PDF document text
    • https://s3.amazonaws.com/wupiwupiwot/18366549422.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4aa24e07-dc6e-4483-8a53-733585005d16/demurapewasin.pdfIn PDF document text
    • https://s3.amazonaws.com/bubeto/wiziwiwadizuwubukir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16977a3a-c578-450d-813b-4dfcb8c09bf2/toyota_corolla_2009_battery_change.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://scripts.sil.org/OFLIn PDF document text
    • http://www.geocities.com/mitra_anirban/hobbies.htmGNUIn PDF document text
    • http://www.gnu.org/copyleft/gpl.htmRegularIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e959.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE959 6048 bytes
SHA-256: 22f9e2930a266a534cbb0e8a6e4d71155463a2d243b8eeae3ed1e900b8f225bc
font_01_sfnt_off0000fdf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF5 9060 bytes
SHA-256: cf8ad4ac95e57c41aa2bfbb7985da84847d131d9affda6df4f30e90c6e805deb
font_02_sfnt_off00011b5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B5A 12320 bytes
SHA-256: 576511e83ec181a01fdee826069dafb73ccf19147abaeebf8055bc0a9c4ad8bd