Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d7c19a20ee61c96…

MALICIOUS

PDF

33.8 KB Created: 2020-08-12 14:08:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 22bd857af15de4f387332787d376e5ad SHA-1: 8ef252e87253bb4604c679d2d7ca03c3d36cfbb6 SHA-256: 9d7c19a20ee61c9691a78c40ecc192756f3eceffe19217ceee7abc107ff84c43
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link farm with numerous embedded URLs, including a known malicious redirector at 'https://ttraff.ru/pify?keyword=bartleby+the+scrivener+pdf+download'. The document body, though heavily obfuscated, appears to be a lure for downloading content, aligning with the heuristic findings of a malicious redirector and a link farm. The ML classifier strongly supports the malicious nature of this PDF.

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://ttraff.ru/pify?keyword=bartleby+the+scrivener+pdf+download
    • http://files.vaaec.org/uploads/1/3/1/4/131483719/zezutazezapudo.pdf
    • http://files.recoveryofhistory.com/uploads/1/3/1/4/131412558/3437718.pdf
    • http://taramez.starfishlearningjourney.com/uploads/1/3/1/3/131383544/5669129.pdf
    • https://cdn.shopify.com/s/files/1/0445/7683/3700/files/assembly_language_programming_8085_examples.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/potiwabuvufepatene.pdf
    • https://cdn.shopify.com/s/files/1/0432/0490/3073/files/61440788105.pdf
    • https://cdn.shopify.com/s/files/1/0431/0361/7173/files/lesuxoje.pdf
    • https://cdn.shopify.com/s/files/1/0433/5638/9528/files/perspectiva_isometrica_caballera_y_militar.pdf
    • https://cdn.shopify.com/s/files/1/0430/3729/4741/files/votedad.pdf
    • https://cdn.shopify.com/s/files/1/0431/4444/6118/files/fapimakatuledizeraki.pdf
    • https://cdn.shopify.com/s/files/1/0437/1474/0375/files/mathematical_optimization_books.pdf
    • https://cdn.shopify.com/s/files/1/0429/5216/3481/files/gijupitejosuviriw.pdf
    • https://cdn.shopify.com/s/files/1/0434/6295/1077/files/dusuworajanezizivoseku.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004662.bin
54cc35cb7d705bddc1f12203e27a74f90c3cc914ef2f28e27c2bd6f2563d0446
pdf-font-stream PDF embedded font (sfnt) at offset 0x4662 5684 bytes
font_01_sfnt_off000059c9.bin
b97fbd37601dc2671b7d00f94728a54585e47fa1dd6fce19938f7094a12d24bd
pdf-font-stream PDF embedded font (sfnt) at offset 0x59C9 9576 bytes