Malicious PDF — malware analysis report

Static analysis result for SHA-256 8657ba28cdc99f8f…

MALICIOUS

PDF

42.3 KB Created: 2020-11-04 00:58:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd0211766dbc591750e4fc782dc070c7 SHA-1: d58be82952a1099ab6a78ddb52a5b6b570f6ab4a SHA-256: 8657ba28cdc99f8f5e419efafbed94c412319141e350a8bfe8ce9281d03c49c2
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with at least one identified as a malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external PDF links, suggesting a link farm or SEO manipulation tactic. The ML classifier also strongly flagged this PDF as malicious. The embedded URLs likely serve to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ggtraff.ru/123?keyword=pregnant+meme+youtube+yahoo+answers
    • https://rofetavagamufup.weebly.com/uploads/1/3/4/3/134373504/zakasojepo_gikokumudigu_babuxopikele.pdf
    • https://cdn-cms.f-static.net/uploads/4410954/normal_5f980cf4915bb.pdf
    • https://cdn-cms.f-static.net/uploads/4369305/normal_5f9e528df1178.pdf
    • https://cdn-cms.f-static.net/uploads/4384028/normal_5f9888b7075da.pdf
    • https://niramividaro.weebly.com/uploads/1/3/4/5/134517418/besuziwalafipatabud.pdf
    • https://cdn-cms.f-static.net/uploads/4366623/normal_5f8738a85e206.pdf
    • https://cdn-cms.f-static.net/uploads/4384832/normal_5f90824827cea.pdf
    • https://terurudib.weebly.com/uploads/1/3/4/3/134381327/69aef4076c5817.pdf
    • https://cdn-cms.f-static.net/uploads/4369143/normal_5f8d7bb5d24a9.pdf
    • https://cdn-cms.f-static.net/uploads/4366625/normal_5f990a99790cf.pdf
    • https://dirigesibujov.weebly.com/uploads/1/3/0/9/130969991/degitotevub-kusuvojivop-bomiwejirex-xelafusapij.pdf
    • https://cdn-cms.f-static.net/uploads/4368469/normal_5f8f354fca9c9.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/kasuwevovog/owen_valley_high_school_yearbook.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000065a6.bin
775fb92e5c57c509a1a11345d7bff1b8ee86cad8ecb7a892cfddb2d1ecb60e95
pdf-font-stream PDF embedded font (sfnt) at offset 0x65A6 5400 bytes
font_01_sfnt_off000077ef.bin
82569ac09c2d5204ef7593c3a97d7654ab5032b222c4ec15c10217c61c09aac5
pdf-font-stream PDF embedded font (sfnt) at offset 0x77EF 10700 bytes