Malicious PDF — malware analysis report

Static analysis result for SHA-256 5623b164cbdce06a…

MALICIOUS

PDF

44.7 KB Created: 2020-08-24 00:51:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e19dc1f0fd95e482f89a0a2d8e959250 SHA-1: 33357c688def9bc7a0c43338c481df0084c3cd94 SHA-256: 5623b164cbdce06a527c14c602a9661c666a9f6e8e95b88bea4804382f06f0a6
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains numerous embedded links, with a critical heuristic firing indicating a link to known malicious redirector infrastructure. The document body, though partially corrupted, suggests a lure related to an 'imaginary numbers operations worksheet'. The presence of a link farm and the ML classifier's high confidence score further support the malicious classification. The primary attack vector appears to be directing users to malicious sites via embedded links.

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=imaginary+numbers+operations+worksheet
    • http://files.stephenquinlan.net/uploads/1/3/0/8/130874233/36952.pdf
    • http://wedegam.schylerthepotter.com/uploads/1/3/1/3/131383629/fovogejawuxowud-kegizon-dabalegi.pdf
    • https://cdn.shopify.com/s/files/1/0433/4052/9816/files/27337014417.pdf
    • https://cdn.shopify.com/s/files/1/0431/6600/7445/files/adversus_haereses_san_ireneo.pdf
    • https://cdn.shopify.com/s/files/1/0435/6522/0003/files/preliminary_report_jmm.pdf
    • https://cdn.shopify.com/s/files/1/0435/3762/9348/files/5894820753.pdf
    • https://cdn.shopify.com/s/files/1/0429/2257/3990/files/feelings_and_emotions_chart.pdf
    • https://cdn.shopify.com/s/files/1/0432/2007/4663/files/gusaneruruzor.pdf
    • https://cdn.shopify.com/s/files/1/0431/3976/0285/files/git_diff_specific_file.pdf
    • https://cdn.shopify.com/s/files/1/0441/2129/2952/files/63310016284.pdf
    • https://cdn.shopify.com/s/files/1/0437/8922/2045/files/nisezedef.pdf
    • https://cdn.shopify.com/s/files/1/0431/0951/5425/files/2755490602.pdf
    • https://cdn.shopify.com/s/files/1/0440/6696/3621/files/jikipiwewukowanimebivavaw.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000062bd.bin
a557bb5dd1ad74f1567d98b0e4147ad2e05ae0b4c4852934b380bcad4fb48dfc
pdf-font-stream PDF embedded font (sfnt) at offset 0x62BD 5420 bytes
font_01_sfnt_off00007506.bin
90eb78e8cfee8cfe9a115a9ade42e9d9812ad653c844d072ee051b48ebc04b24
pdf-font-stream PDF embedded font (sfnt) at offset 0x7506 10176 bytes
font_02_sfnt_off000097e9.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x97E9 4324 bytes