Malicious PDF — malware analysis report

Static analysis result for SHA-256 83bc4f2b6c8e1b71…

MALICIOUS

PDF

46.9 KB Created: 2020-09-19 17:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 52fca89f90270d9c51ab98c80b4c6018 SHA-1: dcecb7f0cf7f6cd06e9367a83ec6b34b200e4e74 SHA-256: 83bc4f2b6c8e1b71b3cc07f6516d81ba501cf44557ff1a3e924ccf1b0a533f09
184 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and routes users through malicious redirector infrastructure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.me/wix?keyword=confidence+interval+example+in+real+life In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://527b0d36-6f87-48bc-be56-6a7c92205b42.filesusr.com/ugd/83d902_9d68a73aad5941409b7baec7ec890218.pdf?index=trueIn PDF document text
    • https://ebdc77ac-c9da-4b46-8ba7-1fee8f80434e.filesusr.com/ugd/405339_01bd02ba8be24fdab5f9bde864c397ea.pdf?index=trueIn PDF document text
    • https://f02f8ed3-4241-4f00-a003-32bf9914e47b.filesusr.com/ugd/7ef0dc_54ede5fb3d4040cab3605982a237b012.pdf?index=trueIn PDF document text
    • https://e93613c7-2b56-42e0-b8db-c51d780e1b49.filesusr.com/ugd/221eaa_935f4e98cd0e4f4a84afcd50aee82a23.pdf?index=trueIn PDF document text
    • https://03e29398-f78e-4351-89a2-d6c9a2eadae6.filesusr.com/ugd/361045_e7ca39635fac493a909344bc2fc5a3af.pdf?index=trueIn PDF document text
    • https://e6df4f85-b8e6-402f-a49b-0f0177de2496.filesusr.com/ugd/501a20_82a0f8b49e64498d840fb191f6931a84.pdf?index=trueIn PDF document text
    • https://22f94b0a-d949-4310-8173-ce50e57b206d.filesusr.com/ugd/02ccf7_d275b32ac0e643aaa501c9384c4490b7.pdf?index=trueIn PDF document text
    • https://f6d50370-17bb-4440-9b3a-6b0671c8472c.filesusr.com/ugd/c4dbd3_fb2a8cb554774cb8a207334aa28b8bab.pdf?index=trueIn PDF document text
    • https://5244ef86-9897-4942-9e2d-67ff1e6d38b7.filesusr.com/ugd/3bbd68_934a63a5b1704c5f95e21ce07a65d1fa.pdf?index=trueIn PDF document text
    • https://0aa2233b-4f98-4769-a3a6-910106ba4287.filesusr.com/ugd/4d935e_da53094a65d94a3cb9476b070e13cd86.pdf?index=trueIn PDF document text
    • https://ad3689b1-6816-4885-a43d-8eaa4d2010f6.filesusr.com/ugd/34e21e_3397c176a40c49b281e22589eff95192.pdf?index=trueIn PDF document text
    • https://ab8b101d-ea10-455d-8f1a-095971b25ec9.filesusr.com/ugd/ac8c68_efc5a58d7e554f918dca89bcd1238d25.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000068ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x68EA 5064 bytes
SHA-256: f64d72285f1ac1486dda1632ed2de97a9c264cf605611cea8f317c155a6d671c
font_01_sfnt_off00007a11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7A11 10664 bytes
SHA-256: a6ddea80b1d8b3adf49e16439826a0c536092b2c3743fac4361a1067af1de49e
font_02_sfnt_off00009e71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9E71 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361