Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa76b7cc44c648f…

MALICIOUS

PDF

43.2 KB Created: 2020-08-19 08:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1ed8cc6327e983e667b699815120c76a SHA-1: 6df86be066d98e7d5e581275a7a5f44e4b7bbf11 SHA-256: 4fa76b7cc44c648fd23098911e864986acc442d7f7bf89b9cccf794933a8d05f
152 Risk Score

Malware Insights

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

The PDF document contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains text related to an 'application letter' and the malicious URL, suggesting a lure to trick users into clicking through to a malicious site. The presence of a link farm further supports the malicious intent.

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.cc/pify?keyword=application+letter+for+any+position+format
    • http://files.owencountyfair.com/uploads/1/3/2/8/132814136/e48dcef7f1df7.pdf
    • http://files.gaiteway.org/uploads/1/3/1/1/131164446/zopepabel.pdf
    • http://momosulo.stephanieespinal.com/uploads/1/3/1/1/131164250/d264e72258.pdf
    • https://cdn.shopify.com/s/files/1/0431/8514/3969/files/4980190055.pdf
    • https://cdn.shopify.com/s/files/1/0432/0516/5216/files/fox_tv_guide_schedule_tonight.pdf
    • https://cdn.shopify.com/s/files/1/0431/7757/4562/files/81583548003.pdf
    • https://cdn.shopify.com/s/files/1/0433/0923/6374/files/28652674698.pdf
    • https://cdn.shopify.com/s/files/1/0431/9812/0094/files/mirozadagozazanol.pdf
    • https://cdn.shopify.com/s/files/1/0429/8843/7655/files/famulumisideri.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/7082322425.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/zetuvoveluganimuwejipas.pdf
    • https://cdn.shopify.com/s/files/1/0430/3673/7699/files/12462441060.pdf
    • https://cdn.shopify.com/s/files/1/0429/8647/1587/files/aid_and_attendance_form.pdf
    • https://cdn.shopify.com/s/files/1/0428/3678/7356/files/jitolelomuzasixazewo.pdf
    • https://cdn.shopify.com/s/files/1/0432/5743/0176/files/83351566938.pdf
    • https://cdn.shopify.com/s/files/1/0431/9110/7742/files/ganelegifeju.pdf
    • https://cdn.shopify.com/s/files/1/0427/9071/5548/files/vewigiwojati.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_off00006ac7.bin
6e6d4cd3a4c8f7f8d83aa7f8c82ed3e7f3510ad8322378368b1fac077f831ead
pdf-font-stream PDF embedded font (sfnt) at offset 0x6AC7 5252 bytes
font_01_sfnt_off00007c8d.bin
bcda1d2fe9a8c14aee8b20991a30c554e383a342e6f0e93fd0560e52cd7dbd74
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C8D 10120 bytes