Malicious PDF — malware analysis report

Static analysis result for SHA-256 a33f1aa3b0f100f4…

MALICIOUS

PDF

43.4 KB Created: 2020-09-01 06:55:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1e16a46f4277f33eec2b9bf82b160fe8 SHA-1: 55b80a7a3d5e05e51993f194264dbd7ade2eaa17 SHA-256: a33f1aa3b0f100f40f22078a8394e189ba4294e1bc0a0804f12ff112b00b667a
152 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, specifically pointing to 'https://ttraff.cc/wix?keyword=video+calling+apps+free++for+android'. This URL is embedded within the document body, suggesting a social engineering lure to trick users into visiting the malicious site. The presence of a large number of external PDF links, many hosted on Shopify, indicates a link farm designed to improve SEO for malicious content. 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.cc/wix?keyword=video+calling+apps+free++for+android
    • https://cdn.shopify.com/s/files/1/0431/4490/4865/files/kegepofabi.pdf
    • https://cdn.shopify.com/s/files/1/0463/2326/9792/files/blister_in_the_sun_ringtone_free.pdf
    • https://cdn.shopify.com/s/files/1/0430/9306/5881/files/problematical_recreations.pdf
    • https://cdn.shopify.com/s/files/1/0428/7614/1731/files/sivexojagimuzobov.pdf
    • https://cdn.shopify.com/s/files/1/0433/3889/1419/files/download_file_yasin_dan_tahlil.pdf
    • https://cdn.shopify.com/s/files/1/0430/7219/2669/files/articles_with_geographical_names_test.pdf
    • https://static.usrfiles.com/ugd/b8c837_b5b202edd1044a25b199b1d41445b8c9.pdf
    • https://static.usrfiles.com/ugd/b8c837_a5af9972d0f448f3874f7d3039e8f891.pdf
    • https://cdn.shopify.com/s/files/1/0430/6419/7273/files/podcast_rss_feed_generator.pdf
    • https://cdn.shopify.com/s/files/1/0435/7593/5134/files/nisamodenarisodixex.pdf
    • https://cdn.shopify.com/s/files/1/0428/5045/1623/files/xijufituwazepi.pdf
    • https://cdn.shopify.com/s/files/1/0463/3604/9313/files/bach_cello_suite_1_prelude_guitar_tab.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_off00006b08.bin
567e9cee381f19f60e6c2f33ce47d1dc6ccc956489d608351bdb4c234bab2c7d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6B08 5288 bytes
font_01_sfnt_off00007d19.bin
2ea7bdab261ff013eb4727b3f71e2c245d086b916a8e9c6a0e76062846480d77
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D19 10524 bytes