Malicious PDF — malware analysis report

Static analysis result for SHA-256 103c9c823583a021…

MALICIOUS

PDF

39.9 KB Created: 2020-07-30 15:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8505e22801daa993efb7bdeb7681efe2 SHA-1: f991f23b82a13ff7db8aed2400e2edcad9458ee7 SHA-256: 103c9c823583a021263f3689807678e815c8c9f3a21180f478e4ce128b399b32
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, appears to be a lure related to educational worksheets, likely intended to trick users into visiting the malicious URLs. No scripts were extracted, but the presence of multiple external links suggests a phishing or redirection attack.

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=simple+present+tense+worksheet+pdf+for+grade+3
    • http://files.opensezme.net/uploads/1/3/1/4/131482950/pivavama-fujafanewawubu.pdf
    • http://files.mssallyschultz.com/uploads/1/3/2/3/132303388/jogijelajox_sirikag_wugugiwimubapi.pdf
    • http://files.alisoviejovet.com/uploads/1/3/1/8/131860125/gasidinezoraj.pdf
    • http://files.130th.org/uploads/1/3/1/3/131379246/779e5.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/2065/6545/files/60470217249.pdf
    • https://cdn.shopify.com/s/files/1/0436/4389/5958/files/bukuwobibaraburiweb.pdf
    • https://cdn.shopify.com/s/files/1/0433/8896/0919/files/69733179200.pdf
    • https://cdn.shopify.com/s/files/1/0431/1177/6416/files/70328491059.pdf
    • https://cdn.shopify.com/s/files/1/0428/1283/3959/files/mavaderinifijuwekas.pdf
    • https://cdn.shopify.com/s/files/1/0430/8808/5145/files/5718540634.pdf
    • https://cdn.shopify.com/s/files/1/0439/9644/6878/files/dovidu.pdf
    • https://cdn.shopify.com/s/files/1/0430/3667/2162/files/dedoperafadekibanonabugu.pdf
    • https://cdn.shopify.com/s/files/1/0431/2222/9397/files/lidegaso.pdf
    • https://cdn.shopify.com/s/files/1/0428/7247/1718/files/94120183738.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005db9.bin
e38cc4793211904c774c35bc1ec7be622831f1ac33ff1cf32fdece25deabfa5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DB9 5664 bytes
font_01_sfnt_off000070d9.bin
a61069bd00a1acc84ee565159f6966f6efc602237d2a3646913559c440667ab2
pdf-font-stream PDF embedded font (sfnt) at offset 0x70D9 9880 bytes