Malicious PDF — malware analysis report

Static analysis result for SHA-256 26bd82b083dabbeb…

MALICIOUS

PDF

45.1 KB Created: 2020-08-04 01:51:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fc43a7b03f205f2d4b55d665604f7bd1 SHA-1: ed96d7116bca0e39ff90fc617de685a01e8914b9 SHA-256: 26bd82b083dabbeb9a2769070ec22d41c6d9a3a736b94b44867d1a300cfba3c8
152 Risk Score

Malware Insights

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

The PDF contains a high number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains the URL for the redirector and appears to be a lure related to 'equivalent fractions worksheets grade 3 pdf'. The ML classifier strongly indicates maliciousness. The primary attack pattern involves redirecting the user to a malicious site.

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.cc/pify?keyword=equivalent+fractions+worksheets+grade+3+pdf
    • http://files.culinaryvacationsinc.com/uploads/1/3/1/4/131437924/donuxowodunejuvito.pdf
    • http://rejol.kenrubitskyassociates.com/uploads/1/3/0/8/130815009/5178666.pdf
    • http://pukul.rabbiklein.com/uploads/1/3/1/4/131453645/sokitabumev.pdf
    • https://cdn.shopify.com/s/files/1/0438/8818/1400/files/tolivuxikoxu.pdf
    • https://cdn.shopify.com/s/files/1/0439/4716/3806/files/fepaxozowilude.pdf
    • https://cdn.shopify.com/s/files/1/0430/4017/8333/files/jobavudonitomi.pdf
    • https://cdn.shopify.com/s/files/1/0433/3050/2806/files/bowiziwewepuzam.pdf
    • https://cdn.shopify.com/s/files/1/0429/6520/5141/files/rixenegekuvovefalulo.pdf
    • https://cdn.shopify.com/s/files/1/0430/4194/7801/files/48642455260.pdf
    • https://cdn.shopify.com/s/files/1/0434/2880/6808/files/2088081374.pdf
    • https://cdn.shopify.com/s/files/1/0434/3077/2901/files/leleguvawana.pdf
    • https://cdn.shopify.com/s/files/1/0433/8722/4214/files/15990742949.pdf
    • https://cdn.shopify.com/s/files/1/0430/9018/2304/files/wivuxokirijaxibofaxusik.pdf
    • https://cdn.shopify.com/s/files/1/0429/3882/6908/files/41864538156.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_off00007110.bin
fdd32298caabdc092a6d6942eaf61f7f378bfcbe72c8c2286109ce5f8048d1b9
pdf-font-stream PDF embedded font (sfnt) at offset 0x7110 5880 bytes
font_01_sfnt_off00008526.bin
2f1f0b3e4a3c9c60ff0978e64c47085b6a85287d7acc411edf7395f6811b2cd9
pdf-font-stream PDF embedded font (sfnt) at offset 0x8526 9924 bytes