Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bb1c700a8a2e9a3…

MALICIOUS

PDF

42.3 KB Created: 2020-08-09 08:04:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cf5aa656c077e0dcf91453a8bb2817d2 SHA-1: 7fa84ec069a0339947de353d03c808b6224f7790 SHA-256: 4bb1c700a8a2e9a39cba7527757dd2ef7d207b5fe5366b2f65dfe49efbad3959
152 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded links, with one specifically pointing to a known malicious redirector infrastructure. The document body, though heavily obfuscated, contains the same URL, suggesting an attempt to lure users to malicious content or engage in SEO manipulation. The ML classifier also strongly indicated maliciousness.

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=accounting+and+finance+management+pdf
    • http://files.happycapehostel.com/uploads/1/3/2/6/132683251/rimijosunex.pdf
    • http://files.hillcountrygardener.com/uploads/1/3/2/6/132682758/dikinojagobowad.pdf
    • http://bugitip.dentalinstrumentcenter.com/uploads/1/3/0/7/130776485/9548924.pdf
    • https://cdn.shopify.com/s/files/1/0440/7663/0181/files/dufegopomabanabo.pdf
    • https://cdn.shopify.com/s/files/1/0430/7006/2754/files/fesoweximowupobin.pdf
    • https://cdn.shopify.com/s/files/1/0433/8457/0019/files/setedavagukigomopulo.pdf
    • https://cdn.shopify.com/s/files/1/0432/8259/6004/files/55025258542.pdf
    • https://cdn.shopify.com/s/files/1/0428/4488/1059/files/48078887011.pdf
    • https://cdn.shopify.com/s/files/1/0434/0213/3667/files/basic_korean_language_learning.pdf
    • https://cdn.shopify.com/s/files/1/0430/9372/1255/files/human_psychology_books_free_download_in_urdu.pdf
    • https://cdn.shopify.com/s/files/1/0433/7994/9718/files/97191955911.pdf
    • https://cdn.shopify.com/s/files/1/0431/9117/3278/files/monitozadodowuku.pdf
    • https://cdn.shopify.com/s/files/1/0433/5792/9622/files/xepunukakonaximudepawa.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_off000067a9.bin
c1eca4e65df2d4b656d6bac10b57beadfd6336d617d270a2e432851399b18ca5
pdf-font-stream PDF embedded font (sfnt) at offset 0x67A9 5156 bytes
font_01_sfnt_off0000792d.bin
a747477597718ef77cea539300c0874f802c9ca6b6b7fc7733f14a0db009fd97
pdf-font-stream PDF embedded font (sfnt) at offset 0x792D 10304 bytes