Malicious PDF — malware analysis report

Static analysis result for SHA-256 10ecce4c8f2d0119…

MALICIOUS

PDF

46.3 KB Created: 2020-09-01 06:00:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a9298cf7255984c5ad6eb0bda37db7b4 SHA-1: 67f722bae1dc819dd69ea56daa8494b4bc5152d0 SHA-256: 10ecce4c8f2d011985d911959098ce4d529317a89f3dddfad43b5f96ce756401
154 Risk Score

Malware Insights

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

The PDF contains embedded links, with one prominent URL identified as a malicious redirector. The document body, though heavily obfuscated, contains text suggesting it is related to 'bksb english diagnostic answers', indicating a lure to trick users into clicking the malicious link. The ML classifier also strongly flagged this PDF as malicious.

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=bksb+english+diagnostic+answers
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/0bcf16_1f7fa7cb8a3c4afdabef5fde83a35aef.pdf
    • https://static.usrfiles.com/ugd/4f270c_176244fe62fd4e3a9bc10429a82bd5f8.pdf
    • https://static.usrfiles.com/ugd/12dc78_30b628c58ee24ef1b74d2dd860017937.pdf
    • https://static.usrfiles.com/ugd/c75f60_d69039c53a374314af1f261ea7291a8c.pdf
    • https://cdn.shopify.com/s/files/1/0432/3134/6856/files/39143346261.pdf
    • https://cdn.shopify.com/s/files/1/0428/4419/2935/files/xonifovoxeveban.pdf
    • https://cdn.shopify.com/s/files/1/0435/9805/3539/files/rijududodabikitated.pdf
    • https://cdn.shopify.com/s/files/1/0434/0298/5637/files/rufobusomu.pdf
    • https://cdn.shopify.com/s/files/1/0435/7269/1099/files/kawasaki_disease_guidelines_uk.pdf
    • https://cdn.shopify.com/s/files/1/0437/0923/5353/files/asciidoc_page_break.pdf
    • https://cdn.shopify.com/s/files/1/0429/8535/7463/files/54114061528.pdf
    • https://cdn.shopify.com/s/files/1/0437/1356/0727/files/zuvozakidixanelabenevi.pdf
    • https://cdn.shopify.com/s/files/1/0432/5467/7668/files/askep_kasus_bblr.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_off000076fe.bin
af3f172686a8c238cc01ecb39e81da4a1c0065eb40f7ae525463da429a66733c
pdf-font-stream PDF embedded font (sfnt) at offset 0x76FE 5544 bytes
font_01_sfnt_off000089e9.bin
98b8c2ce8dff6cd9647d0e9ee625cc83fdf6b1b4bbbecdfe0e3a434ad171e186
pdf-font-stream PDF embedded font (sfnt) at offset 0x89E9 10024 bytes