Malicious PDF — malware analysis report

Static analysis result for SHA-256 c906728dfb32331a…

MALICIOUS

PDF

40.2 KB Created: 2020-08-24 10:40:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d8dc5d83b031cdd6c3021915168eaac6 SHA-1: 95db5ae069362069e8e7ca8d61149e4ab95a02ce SHA-256: c906728dfb32331a6c6756c55e887ac3260fe459d577d472108d496b4251b192
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a link to a redirector infrastructure, which is a common technique for delivering malicious payloads. The document body, though heavily obfuscated, contains text related to 'Korean drama app offline' and a URL that appears to be part of a link farm designed to attract search engine traffic. The ML classifier strongly indicates maliciousness, and the presence of numerous embedded URLs, including one pointing to known malicious redirector infrastructure, supports this assessment.

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=korean+drama++app+offline
    • http://files.lmnaturalhealth.com/uploads/1/3/1/4/131437956/janumabenise.pdf
    • http://zoforat.charmcitypetcrematory.com/uploads/1/3/1/6/131606552/barunututaw-bunaxoxez.pdf
    • https://cdn.shopify.com/s/files/1/0432/7473/1685/files/are_androids_smartphones.pdf
    • https://cdn.shopify.com/s/files/1/0438/7376/3496/files/aulad_bhojpuri_movie_all_song.pdf
    • https://cdn.shopify.com/s/files/1/0432/2213/9041/files/wotirimixipogotive.pdf
    • https://cdn.shopify.com/s/files/1/0432/7302/7749/files/lopovepogujizozerebobug.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tagesagebog.pdf
    • https://cdn.shopify.com/s/files/1/0432/2387/5746/files/11354558533.pdf
    • https://cdn.shopify.com/s/files/1/0433/5471/8358/files/kapona.pdf
    • https://cdn.shopify.com/s/files/1/0431/6718/7108/files/heat_treater_s_guide.pdf
    • https://cdn.shopify.com/s/files/1/0430/7674/7413/files/pays_et_capitale_du_monde.pdf
    • https://cdn.shopify.com/s/files/1/0428/4140/7644/files/inductive_deductive_and_abductive_research_approach.pdf
    • https://cdn.shopify.com/s/files/1/0428/5526/8519/files/antigone_anouilh_english.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_off00006089.bin
6d8e34891515c197d48654235ed5f9e99b86f76730f4a97374e49fbe75d7cc96
pdf-font-stream PDF embedded font (sfnt) at offset 0x6089 4976 bytes
font_01_sfnt_off00007160.bin
f8c49e91539e7bdf64d5224c5df344a8b5e4daadc4c21989b719c3f891e7bc59
pdf-font-stream PDF embedded font (sfnt) at offset 0x7160 10244 bytes