Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f61d71c2dadc6a9…

MALICIOUS

PDF

46.3 KB Created: 2020-08-26 22:10:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: acde648cbca0029c5d38cb4ff9d6635d SHA-1: 21911565ea3ffc6fb96ffe752b2a71b66b9e14f8 SHA-256: 0f61d71c2dadc6a98d0d438303a6dca4d016167879f1967144dcc5aeecf093bb
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, disguised within text that appears to be exam questions. The PDF also hosts a large number of external links, many of which point to benign Shopify URLs, suggesting a link farm or SEO manipulation tactic. The ML classifier strongly indicates maliciousness, and the presence of embedded URLs supports a phishing or redirection attack pattern.

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=police+constable+exam+questions+and
    • http://files.upstatecluttercoach.com/uploads/1/3/2/8/132814306/9955826.pdf
    • http://files.worldofsong.com/uploads/1/3/0/7/130776607/5210395.pdf
    • http://jimixezuv.lasvegasmetrohonorguard.com/uploads/1/3/0/7/130740113/1612767.pdf
    • http://files.latina1059fm.com/uploads/1/3/0/8/130814346/makexakadolax_kiruvamidukaji.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/3189/4944/files/2019_monthly_calendar_template_word_october.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/66541571973.pdf
    • https://cdn.shopify.com/s/files/1/0445/3980/5855/files/naruto_shippuden_mobile_games_free.pdf
    • https://cdn.shopify.com/s/files/1/0437/2915/8295/files/11416711506.pdf
    • https://cdn.shopify.com/s/files/1/0437/1054/6070/files/changing_between_fractions_decimals_and_percentages_worksheets.pdf
    • https://cdn.shopify.com/s/files/1/0434/0921/1557/files/24391578258.pdf
    • https://cdn.shopify.com/s/files/1/0428/2040/3356/files/28619980153.pdf
    • https://cdn.shopify.com/s/files/1/0429/2080/4511/files/5095951678.pdf
    • https://cdn.shopify.com/s/files/1/0462/6389/4173/files/lucy_fairy_tail_naked.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_off0000766f.bin
cbb1e2f024cc87f6999efd8d99951aad2675a0fd8a53965c94f5c9fb8cf3075e
pdf-font-stream PDF embedded font (sfnt) at offset 0x766F 5324 bytes
font_01_sfnt_off00008867.bin
3cd9850ad93df06355327bbc352c3188cd6fc21d0998ec8ebba72d2ba207292c
pdf-font-stream PDF embedded font (sfnt) at offset 0x8867 10528 bytes