Malicious PDF — malware analysis report

Static analysis result for SHA-256 23509bc9abe2c2a9…

MALICIOUS

PDF

33.9 KB Created: 2020-08-13 01:30:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 23fb5f86cd3792f0265ec0de85980e81 SHA-1: a951395f515c656b55733e0dd080639d81958be8 SHA-256: 23509bc9abe2c2a9643756b863400c8dc770c576a91e3aa2dc825235265b168c
154 Risk Score

Malware Insights

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

The PDF contains a link that redirects to a known malicious infrastructure, disguised as a worksheet. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains the URL that triggers the malicious redirect. No scripts were extracted, limiting the analysis of further stages.

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=assertive+communication+worksheet+pdf
    • http://files.mychoice-thefilm.com/uploads/1/3/2/8/132815181/vanumajogivab.pdf
    • http://files.startoonz.com/uploads/1/3/2/6/132681880/9973a3ec95.pdf
    • http://files.crossfitliveloud.com/uploads/1/3/0/9/130969352/5038501.pdf
    • http://files.raggedmountainrunning.com/uploads/1/3/0/7/130776273/3ef5718.pdf
    • https://cdn.shopify.com/s/files/1/0432/5713/5264/files/zoleraxamopibudusatosawu.pdf
    • https://cdn.shopify.com/s/files/1/0427/5961/8716/files/27219307252.pdf
    • https://cdn.shopify.com/s/files/1/0433/3905/5253/files/binary_options_ebook.pdf
    • https://cdn.shopify.com/s/files/1/0430/6701/5329/files/nirarevemowewofajovereba.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9191/files/nusigovetute.pdf
    • https://cdn.shopify.com/s/files/1/0434/2477/6354/files/wuberesinaxomufi.pdf
    • https://cdn.shopify.com/s/files/1/0434/8762/5369/files/bivosotazemerelurunutepiw.pdf
    • https://cdn.shopify.com/s/files/1/0429/9010/8833/files/62823104211.pdf
    • https://cdn.shopify.com/s/files/1/0434/8621/6344/files/25683237507.pdf
    • https://cdn.shopify.com/s/files/1/0428/4504/4892/files/xajawedowoweloluferof.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_off000046d7.bin
999b976e70e58e5f311732175fcf18c0ba94b8a580665a43fe8efa9d9de124bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x46D7 5568 bytes
font_01_sfnt_off000059b1.bin
f76c1be6396e6d2318b31236d35a70a826236fe5936003f7278796ceeae4f0a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x59B1 9764 bytes