Malicious PDF — malware analysis report

Static analysis result for SHA-256 26a3a81839f701c5…

MALICIOUS

PDF

48.4 KB Created: 2020-08-24 23:41:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fad9e4d1af4f3cf37dedab4d127811e8 SHA-1: 3089bea74c07aebd266f6db057be41927b2bcc31 SHA-256: 26a3a81839f701c5ba9a2d8a1aed425b02a518151bdd21d211aabe5fc025f46f
152 Risk Score

Malware Insights

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

The PDF contains embedded links, with one specifically identified as a malicious redirector pointing to 'ttraff.com'. The document body, though partially corrupted, suggests a lure related to an 'HR appraisal form sample'. The presence of numerous external PDF links, many hosted on Shopify, indicates a link farm strategy. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it's designed for malicious redirection.

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=hr+appraisal+form+sample
    • http://wupof.fotsga.com/uploads/1/3/1/3/131398504/1504405.pdf
    • http://vevufe.autumnlealshopp.com/uploads/1/3/1/4/131407995/2514336.pdf
    • http://files.waterring.net/uploads/1/3/0/9/130969034/wedul.pdf
    • https://cdn.shopify.com/s/files/1/0437/1241/3851/files/7928924247.pdf
    • https://cdn.shopify.com/s/files/1/0439/7219/8558/files/noad_solo_guitar_playing.pdf
    • https://cdn.shopify.com/s/files/1/0434/1458/5509/files/44331541166.pdf
    • https://cdn.shopify.com/s/files/1/0427/6482/8838/files/79564852575.pdf
    • https://cdn.shopify.com/s/files/1/0430/4555/2290/files/5348288689.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/92313200312.pdf
    • https://cdn.shopify.com/s/files/1/0434/7723/7920/files/information_report_examples_year_5.pdf
    • https://cdn.shopify.com/s/files/1/0463/4640/4002/files/please_find_below_additional_information.pdf
    • https://cdn.shopify.com/s/files/1/0437/0651/5611/files/39072093290.pdf
    • https://cdn.shopify.com/s/files/1/0431/9117/3278/files/accuracy_vs_precision_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0427/7311/9143/files/guriworug.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_off000081e2.bin
279c7d7737ec020719a306f65de8c91d112ab26d6a8b73c82aa6b49a75b6fe83
pdf-font-stream PDF embedded font (sfnt) at offset 0x81E2 5008 bytes
font_01_sfnt_off000092cb.bin
45012a393ad58793fde2c0a0ff39c07edcb1215d24bfc1366dead870200827af
pdf-font-stream PDF embedded font (sfnt) at offset 0x92CB 10088 bytes