Malicious PDF — malware analysis report

Static analysis result for SHA-256 25a45d4d85f8308d…

MALICIOUS

PDF

52.8 KB Created: 2020-08-05 03:03:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e57d8948809cafb9e75d23a6f1187d5c SHA-1: 3574e768263ace0f617d0d1c421484a5e2244b89 SHA-256: 25a45d4d85f8308d453d004537269a590f103a75210d0e9b26ee23548e20dc0c
154 Risk Score

Malware Insights

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

The PDF contains a malicious redirector link disguised as a link to 'top biography books pdf'. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, contains the URL that leads to the redirector. The primary attack vector appears to be luring users to malicious infrastructure.

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=top+biography+books+pdf
    • http://files.jennifercarrpainting.com/uploads/1/3/1/3/131380870/kolikazilumewin.pdf
    • http://files.birregurrafestival.com/uploads/1/3/0/9/130969764/7ed68f5002a.pdf
    • http://files.goingcoastalns.com/uploads/1/3/1/4/131407887/5383339.pdf
    • http://debobaxo.dammannfarms.com/uploads/1/3/0/8/130874431/todobofowibugom_wekulemapuf.pdf
    • https://cdn.shopify.com/s/files/1/0430/7425/7057/files/dubiguwuvixeveget.pdf
    • https://cdn.shopify.com/s/files/1/0428/4206/3004/files/7915568385.pdf
    • https://cdn.shopify.com/s/files/1/0440/7132/1752/files/xazabenoliral.pdf
    • https://cdn.shopify.com/s/files/1/0435/8491/3565/files/selegigukuvaw.pdf
    • https://cdn.shopify.com/s/files/1/0433/0497/6548/files/bepefobokokiwalakes.pdf
    • https://cdn.shopify.com/s/files/1/0436/1319/2349/files/minutik.pdf
    • https://cdn.shopify.com/s/files/1/0432/1450/4093/files/nutelosumezebepane.pdf
    • https://cdn.shopify.com/s/files/1/0434/2392/4376/files/hernia_inguinalis_anak.pdf
    • https://cdn.shopify.com/s/files/1/0431/6237/0210/files/18762913408.pdf
    • https://cdn.shopify.com/s/files/1/0433/7316/6757/files/kasigasanokorodivezoduvu.pdf
    • https://cdn.shopify.com/s/files/1/0431/0591/0933/files/71026813431.pdf
    • https://cdn.shopify.com/s/files/1/0433/6710/4668/files/62538679938.pdf
    • https://cdn.shopify.com/s/files/1/0433/0664/7717/files/domet.pdf
    • https://cdn.shopify.com/s/files/1/0428/0709/9558/files/kogulupisej.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_off00008fef.bin
60f4e0f91b03ae9d2992fc98006f57f324a440863e69b7db0d6ef529a9b00502
pdf-font-stream PDF embedded font (sfnt) at offset 0x8FEF 5524 bytes
font_01_sfnt_off0000a2bb.bin
192eba33db4266bc4e3cc1b11a68486836c9a1fdf50f3772f2cc972c359779fa
pdf-font-stream PDF embedded font (sfnt) at offset 0xA2BB 10356 bytes