Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d87ad5ffb8e5d17…

MALICIOUS

PDF

41.0 KB Created: 2020-08-21 22:09:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f397aebc97e2cced3b89c5449d5bec55 SHA-1: a9d2d8e20a760b9c57dfc22ae768da9b7d9b2689 SHA-256: 3d87ad5ffb8e5d1750b8304901f807b75a4dff14d2a49f5d0a515a76a94db518
152 Risk Score

Malware Insights

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

The PDF contains a prominent link disguised as a download for 'True caller id apk latest version', which redirects to a malicious URL. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms this behavior. Additionally, the PDF_SEO_LINK_FARM heuristic indicates a large number of outbound links, many hosted on cdn.shopify.com, suggesting a link farm designed to attract traffic. The ML_NYX_PDF_MALICIOUS score further supports the malicious nature of the document.

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=true+caller+id+apk+latest+version
    • http://gajep.backhomebutchershop.com/uploads/1/3/0/8/130873995/zifeweka-subovenofususij-pefuraxixife-bizezimawo.pdf
    • http://walozu.nauticalreplicas.com/uploads/1/3/1/3/131380213/6850463.pdf
    • http://files.wacoceg.org/uploads/1/3/1/4/131438055/dc8ed60d226a.pdf
    • http://vuwedomo.mipalmi.com/uploads/1/3/1/3/131398591/9101217.pdf
    • https://cdn.shopify.com/s/files/1/0437/7319/8487/files/mosobujizojofa.pdf
    • https://cdn.shopify.com/s/files/1/0431/5804/4827/files/21425611237.pdf
    • https://cdn.shopify.com/s/files/1/0437/8863/2213/files/69947729229.pdf
    • https://cdn.shopify.com/s/files/1/0431/0306/0128/files/biography_writing_sample.pdf
    • https://cdn.shopify.com/s/files/1/0434/0459/1254/files/11576681519.pdf
    • https://cdn.shopify.com/s/files/1/0434/4204/5090/files/xetujexataliguwuxolejodo.pdf
    • https://cdn.shopify.com/s/files/1/0449/9534/6590/files/ipl_2020_schedule_players_list_all_team.pdf
    • https://cdn.shopify.com/s/files/1/0430/8631/5671/files/76432748926.pdf
    • https://cdn.shopify.com/s/files/1/0432/4560/0936/files/31880266538.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/29878061118.pdf
    • https://cdn.shopify.com/s/files/1/0429/6579/4965/files/89813693006.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_off00006201.bin
b178b41b41e71227fcce1baed7df8aa144439392fdf071d9b06949a7242311a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x6201 5140 bytes
font_01_sfnt_off00007390.bin
e9289a2368488546dd45bcfb88863f571a087e56570ab9a04983e8cbad8f5ec4
pdf-font-stream PDF embedded font (sfnt) at offset 0x7390 10448 bytes