Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1bca2edbbbb68b6…

MALICIOUS

PDF

42.6 KB Created: 2020-08-24 21:49:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e7f1bdeb00ca64ea2b172d644cc3e63a SHA-1: 3c9f54f14f68b955435ea51cac8ac92ca8d49d2e SHA-256: a1bca2edbbbb68b6687b498647ae8e6d8fc941062ab002fb2bbb4c9a2886f20e
154 Risk Score

Malware Insights

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

The PDF contains a malicious redirector link disguised as calculus olympiad problems. The ML classifier strongly indicates maliciousness, and the PDF structure includes a large number of external links, many hosted on Shopify, likely for SEO manipulation to increase visibility. The primary malicious IOC is the ttraff.com redirector URL.

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=calculus+olympiad+problems+pdf
    • http://files.r2sg.com/uploads/1/3/1/3/131380175/lomalukasuzire.pdf
    • http://vimozi.lakeantoine.org/uploads/1/3/0/7/130775883/880c165790b.pdf
    • https://cdn.shopify.com/s/files/1/0431/0489/5143/files/riguvekirutosemixut.pdf
    • https://cdn.shopify.com/s/files/1/0438/4178/1920/files/oracle_11g_sql_interview_questions_and_answers.pdf
    • https://cdn.shopify.com/s/files/1/0434/6164/0358/files/upstream_english_book_b1.pdf
    • https://cdn.shopify.com/s/files/1/0433/0792/5654/files/nofizokoriwaro.pdf
    • https://cdn.shopify.com/s/files/1/0437/1313/4757/files/oracle_sql_queries_interview_questions_and_answers.pdf
    • https://cdn.shopify.com/s/files/1/0431/8153/9489/files/71411927419.pdf
    • https://cdn.shopify.com/s/files/1/0431/5339/1780/files/43511693449.pdf
    • https://cdn.shopify.com/s/files/1/0428/7250/4483/files/65447981598.pdf
    • https://cdn.shopify.com/s/files/1/0430/5174/5442/files/vizuwejixedezurowonon.pdf
    • https://cdn.shopify.com/s/files/1/0432/2734/9159/files/gevuraguraworugi.pdf
    • https://cdn.shopify.com/s/files/1/0430/4191/5042/files/zejemenamurewotuvexe.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_off00006617.bin
458dad2755ecf56da5a04c4cfff2ee5e247f62292e3203c8f726b4536f51f3fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x6617 5448 bytes
font_01_sfnt_off0000788a.bin
408d22b2703ccfd81d0e2552aa268fdc75a4077896c006f48567e8e1b183b806
pdf-font-stream PDF embedded font (sfnt) at offset 0x788A 11104 bytes