Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa7ab3622146f8d…

MALICIOUS

PDF

71.6 KB Created: 2020-07-31 10:12:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c4a08dadedc74ee4b6e5f8dd31723297 SHA-1: a799c75fb991af55f6171aa585efa608e9f45b5a SHA-256: caa7ab3622146f8dd313f6522b2fa9e2a5f0a579243e8912aa09ffbc6d56d6bd
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains embedded links that redirect to malicious infrastructure, specifically identified by the 'PDF_MALICIOUS_REDIRECTOR_LINK' heuristic. The 'PDF_SEO_LINK_FARM' heuristic further indicates a large number of external links, many pointing to Shopify domains, suggesting an attempt to manipulate search results or distribute malicious content. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool sometimes used to create malicious PDFs.

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.com/pify?keyword=anatomy+and+physiology+animals+pdf
    • http://files.dancecenterint.com/uploads/1/3/1/3/131381614/fovibudakozo.pdf
    • http://files.bacspto.com/uploads/1/3/1/4/131453998/8636046.pdf
    • http://files.mckenzieareadayhomes.com/uploads/1/3/1/4/131453894/937327.pdf
    • https://cdn.shopify.com/s/files/1/0429/5943/7975/files/lobotuzikemovisepe.pdf
    • https://cdn.shopify.com/s/files/1/0429/5950/3519/files/82582028251.pdf
    • https://cdn.shopify.com/s/files/1/0431/1023/6314/files/33327419778.pdf
    • https://cdn.shopify.com/s/files/1/0434/1530/6405/files/71131269234.pdf
    • https://cdn.shopify.com/s/files/1/0430/3618/0634/files/jowejopomavafix.pdf
    • https://cdn.shopify.com/s/files/1/0431/0440/3613/files/belodeloluxikuzozijufurik.pdf
    • https://cdn.shopify.com/s/files/1/0435/2966/6724/files/xirupafasibidunebetozep.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/mowelikuzamutaj.pdf
    • https://cdn.shopify.com/s/files/1/0428/2833/3219/files/50387314271.pdf
    • https://cdn.shopify.com/s/files/1/0433/5140/8799/files/63976063239.pdf
    • https://cdn.shopify.com/s/files/1/0427/7462/6470/files/42951503021.pdf
    • https://cdn.shopify.com/s/files/1/0435/1868/9432/files/82245554589.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_off0000dc59.bin
8babe0364d016bcdeea0eaa7c95b2d67792f3eafbda0ed5362b2b25defa57517
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC59 5120 bytes
font_01_sfnt_off0000ed9b.bin
26b4a179a2c2ee4ca82f8b0d402dde5beec129c4662993f2dee98ba1538abec5
pdf-font-stream PDF embedded font (sfnt) at offset 0xED9B 10316 bytes