Malicious PDF — malware analysis report

Static analysis result for SHA-256 dff146d519f6a23d…

MALICIOUS

PDF

36.7 KB Created: 2020-09-13 07:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 39489299a4fac3b20fd3625c652b8d26 SHA-1: 7134d35fbc50892c261c116ad52358c1b92bb6e6 SHA-256: dff146d519f6a23d28a59e557a7a0c1a45815a30e7a122356a46a29931d1deff
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, identified by the PDF_SEO_LINK_FARM heuristic, pointing to various domains. One prominent link, https://ttraff.link/wix?keyword=avondale+middle+school, is flagged as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains some of these URLs, suggesting the primary purpose is to redirect the user to potentially harmful content.

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.link/wix?keyword=avondale+middle+school
    • http://bumibezo.nejcrwc.com/uploads/1/3/0/7/130739235/kamikifo.pdf
    • http://jidega.pezzafarm.com/uploads/1/3/2/6/132683078/6408784.pdf
    • http://wutawowav.paulmorellimusic.com/uploads/1/3/0/8/130874474/zinagebi-jubujerok-zavenasobu.pdf
    • http://logovubuv.facedoctorscoopers.co.nz/uploads/1/3/1/4/131437089/lekuwedesutaro_majepageza.pdf
    • http://files.catherinehessart.com/uploads/1/3/2/6/132681851/495fb5e.pdf
    • https://us02web.zoom
    • https://cdn.shopify.com/s/files/1/0428/5795/5487/files/70919039880.pdf
    • https://static.usrfiles.com/ugd/d78803_1983456a44f24c04a05d9833e3d218fb.pdf
    • https://static.usrfiles.com/ugd/c7ef1a_d004f764e426476e9ec8d89b8213520f.pdf
    • https://static.usrfiles.com/ugd/3f4b99_dec2b64395dd48d38fe8353316ff7366.pdf
    • https://static.usrfiles.com/ugd/b42fd6_9bff1027da2b4b218f74c6de2f3b1e14.pdf
    • https://static.usrfiles.com/ugd/fc3b0b_32bf17e3d9534bd4a626ff8a669793cc.pdf
    • https://cdn.shopify.com/s/files/1/0433/4020/2142/files/kutidimo.pdf
    • https://cdn.shopify.com/s/files/1/0433/8830/5558/files/979289708.pdf
    • https://cdn.shopify.com/s/files/1/0462/6428/7381/files/louisiana_truck_outfitters.pdf
    • https://cdn.shopify.com/s/files/1/0451/3175/9769/files/star_template_interview.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_off00005109.bin
b9da9b11eba447a75ad18bf56acb03874db86e321de1e448ee3a23da02c3be36
pdf-font-stream PDF embedded font (sfnt) at offset 0x5109 5132 bytes
font_01_sfnt_off0000625f.bin
7de7faad0768932ff633469389b3b5e3d7f1efee64593c2fa1212cf7cedcc320
pdf-font-stream PDF embedded font (sfnt) at offset 0x625F 10484 bytes