Malicious PDF — malware analysis report

Static analysis result for SHA-256 ddb1502a3e49f605…

MALICIOUS

PDF

44.2 KB Created: 2020-08-20 20:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: daf29578f22d23c90aed629d1b188bc3 SHA-1: 43fd38753ead4b7818679fe99e935e2596eaac71 SHA-256: ddb1502a3e49f6050495dfed763a3c6b08b8c5136d679d5dcee25a12f45e4ba2
152 Risk Score

Malware Insights

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

The PDF file contains embedded links, with one pointing to a known malicious redirector. The document body, though partially corrupted, includes text related to 'Topics for group discussion with answers' and the malicious URL, suggesting a lure. The presence of numerous external PDF links further indicates a link farm strategy, likely to obscure the ultimate destination or to improve search engine ranking for malicious content. The ML classifier 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.ru/pify?keyword=topics+for+group+discussion+with+answers
    • http://vokanox.talltechteacher.com/uploads/1/3/2/3/132303382/vojobofok-juxobegoromut-gazol-gevepakilaloro.pdf
    • http://gerakuj.scarboroughmaineyoga.com/uploads/1/3/1/3/131380999/dizufun_mutigum_nipifuva.pdf
    • http://files.rockvillehelp.org/uploads/1/3/1/4/131437443/5649129.pdf
    • http://rexovix.cjbrassica.com/uploads/1/3/0/8/130874075/a35c7ca3844db.pdf
    • https://cdn.shopify.com/s/files/1/0440/3717/7494/files/buwavinu.pdf
    • https://cdn.shopify.com/s/files/1/0438/1189/7504/files/zavamusexukixu.pdf
    • https://cdn.shopify.com/s/files/1/0435/7763/9075/files/second_conditional_exercises_multiple_choice.pdf
    • https://cdn.shopify.com/s/files/1/0432/7568/1947/files/adagio_baermann.pdf
    • https://cdn.shopify.com/s/files/1/0427/4031/8375/files/augusto_cury_livros.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/pejuzesuloroxutebed.pdf
    • https://cdn.shopify.com/s/files/1/0437/8266/8437/files/87378343670.pdf
    • https://cdn.shopify.com/s/files/1/0430/7301/1863/files/85499613945.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/
    • https://cdn.shopify.com/s/files/1/0435/7763/9075/files/second_conditional_exercises_m

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006e9a.bin
d87f1d345274e8e178aaa108bf5b77349d273e1efeffc919fcb14fc0d81485f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E9A 5428 bytes
font_01_sfnt_off00008113.bin
c3ac06a62af7a3828113e366d1332f47a8cf81d8ec17b66a56f753338d218e13
pdf-font-stream PDF embedded font (sfnt) at offset 0x8113 10200 bytes