Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f3ed6601768c0b4…

MALICIOUS

PDF

39.7 KB Created: 2020-09-05 02:44:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 401e10354af910115de9a0bb09c639a4 SHA-1: 205bf9f6790192f5c1e86acb419eb61ec6f25a66 SHA-256: 5f3ed6601768c0b4eaa9fdc8eb2f472171839ca5c5437305d6c3c2e03caa9cc4
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, ttraff.link, which is designed to lure users into clicking on it. The document body, though heavily obfuscated, contains the same URL and appears to be a lure related to educational worksheets. The presence of numerous other links to PDF files, some of which are benign, suggests a link farm or SEO manipulation tactic to disguise the malicious intent. The ML classifier 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.link/wix?keyword=addition+subtraction+worksheet+for+class+4
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/1d5a3f_61497f768b1645be88df8c73c8fbaab1.pdf
    • https://static.usrfiles.com/ugd/b8c837_0d398b0f79434bf4ac344646bc9b8364.pdf
    • https://static.usrfiles.com/ugd/ac51ce_4b0ec03bf13e4bc582f71483ecb90fc7.pdf
    • https://static.usrfiles.com/ugd/b8c837_f387e4aade1d4fa9b16ff9bab8f379b8.pdf
    • https://static.usrfiles.com/ugd/5fd5c1_127dfb0557554fbaa45d8aedacd50204.pdf
    • https://cdn.shopify.com/s/files/1/0464/3274/7672/files/dewalt_720_radial_arm_saw_manual.pdf
    • https://cdn.shopify.com/s/files/1/0431/0056/9753/files/telejojozuwibigavurutuzo.pdf
    • https://cdn.shopify.com/s/files/1/0433/7070/9142/files/3999998909.pdf
    • https://cdn.shopify.com/s/files/1/0437/0232/1307/files/8_facts_about_barberton_makhonjwa_mountains.pdf
    • https://cdn.shopify.com/s/files/1/0437/3744/8609/files/rectangular_form_calculator.pdf
    • https://cdn.shopify.com/s/files/1/0436/7728/6553/files/23178941312.pdf
    • https://cdn.shopify.com/s/files/1/0435/8085/0335/files/carpal_tunnel_syndrome_patient.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_off00005a12.bin
1cb6d79fbc52cf08b72cff959943512caeba55803d65635511a1d25f6e2d9064
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A12 5484 bytes
font_01_sfnt_off00006cc9.bin
0866623f3e4959d061b8476758072db0d40f1aaaa81b079ad92ad811fbaae69f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CC9 10468 bytes