Malicious PDF — malware analysis report

Static analysis result for SHA-256 e2532a80793eb038…

MALICIOUS

PDF

43.7 KB Created: 2020-09-01 09:39:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ed23577f382d2a7c5b642e080de47cc3 SHA-1: 4c18a6e5020182c5f6a04ef28dd9908515ac15f3 SHA-256: e2532a80793eb03858e3d5ea08e5da0c709cd3fe748ee350460760897777f0fb
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 a study guide, which is a common social engineering tactic to trick users into visiting malicious sites. The ML classifier strongly indicated maliciousness, and the PDF was flagged for containing a link farm pointing to external resources, including the identified redirector. The document body, though heavily obfuscated, contains the URL that is also present in the heuristics and IOCs.

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=connecticut+driver%2527+s+permit+test+study+guide
    • https://static.usrfiles.com/ugd/6f53d7_aa87c0c6f1b44caf9ef852895f4250aa.pdf
    • https://static.usrfiles.com/ugd/12f4eb_32e5451ee19b486c95ea30f71ede743a.pdf
    • https://static.usrfiles.com/ugd/de02f3_86074087b33a4021b9604ee7de082399.pdf
    • https://cdn.shopify.com/s/files/1/0436/0785/1171/files/electronically_sign_app.pdf
    • https://cdn.shopify.com/s/files/1/0428/9318/1095/files/medicine_names_and_uses_in_tamil.pdf
    • https://cdn.shopify.com/s/files/1/0434/9178/6918/files/futolotunakese.pdf
    • https://cdn.shopify.com/s/files/1/0438/4777/8469/files/81389005311.pdf
    • https://cdn.shopify.com/s/files/1/0437/3318/8762/files/88447200344.pdf
    • https://cdn.shopify.com/s/files/1/0428/6509/8908/files/sadebuvisumikuxaxugij.pdf
    • https://cdn.shopify.com/s/files/1/0434/4394/5628/files/adobe_acrobat_reader_9_free_linux.pdf
    • https://cdn.shopify.com/s/files/1/0430/3034/7938/files/93178725322.pdf
    • https://cdn.shopify.com/s/files/1/0433/4754/2175/files/39673618845.pdf
    • https://cdn.shopify.com/s/files/1/0437/1116/8664/files/46684149857.pdf
    • https://cdn.shopify.com/s/files/1/0430/1262/0447/files/33006521661.pdf
    • https://cdn.shopify.com/s/files/1/0428/5923/3443/files/75592048149.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_off00006beb.bin
5174dfe46f3dff43090b5e297e18daa2dbbc00bb4ec8c918376cb23f17abd646
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BEB 5252 bytes
font_01_sfnt_off00007dc9.bin
1f93b3f6014bb991e6d69c97d3a6be369405745c4ab0f855aee2a96afe6843f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7DC9 10504 bytes