Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a16a8da8b526bc5…

MALICIOUS

PDF

49.1 KB Created: 2020-07-25 22:51:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dd72444551c4d58e91ba31cd2d014058 SHA-1: a49b92bb19c3b0109e9ce0eb06379c5cdf21ed78 SHA-256: 5a16a8da8b526bc516793842ff292600aeea896278d06f84e8b62ed0dfd09e7a
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating a redirector to known malicious infrastructure. The document body, though heavily obfuscated, appears to be a lure related to 'linear equations worksheets for 8th grade'. The presence of a malicious redirector URL and the link farm structure strongly suggest a phishing or malicious redirection attempt.

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.ru/pify?keyword=linear+equations+worksheets+for+8th+grade
    • http://files.massbuyinggroup.com/uploads/1/3/0/9/130969552/2968782.pdf
    • http://files.beblessedwellness.com/uploads/1/3/2/6/132681985/f23d5983046a48f.pdf
    • http://files.midmichyouthultimate.com/uploads/1/3/2/6/132681378/6d1d1.pdf
    • https://cdn.shopify.co
    • https://cdn.shopify.com/s/files/1/0432/1096/5147/files/wimiwuzoviwa.pdf
    • https://cdn.shopify.com/s/files/1/0431/0673/0144/files/88173117304.pdf
    • https://cdn.shopify.com/s/files/1/0429/9322/1783/files/8152297183.pdf
    • https://cdn.shopify.com/s/files/1/0434/5744/6038/files/29356065827.pdf
    • https://cdn.shopify.com/s/files/1/0429/6795/7658/files/kitewixixumoweber.pdf
    • https://cdn.shopify.com/s/files/1/0430/0088/9507/files/dusozepinis.pdf
    • https://cdn.shopify.com/s/files/1/0432/2564/5211/files/25318099103.pdf
    • https://cdn.shopify.com/s/files/1/0431/3546/7669/files/zegakigulopajebeb.pdf
    • https://cdn.shopify.com/s/files/1/0428/9894/8255/files/segeninapiweli.pdf
    • https://cdn.shopify.com/s/files/1/0433/0278/1083/files/nejuwavibapuk.pdf
    • https://cdn.shopify.com/s/files/1/0434/4948/3426/files/xatadetupojidojuz.pdf
    • https://cdn.shopify.com/s/files/1/0429/3656/5923/files/91008284052.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_off0000761f.bin
84dca9a7c5331de518ea39d0cf5e919cf46287a5a22f7ce6b03ac2437065489f
pdf-font-stream PDF embedded font (sfnt) at offset 0x761F 5436 bytes
font_01_sfnt_off0000889b.bin
615e5e65c87e65af96d6fbeba4a403ac100c021796f576274c0cc50f52a7cef7
pdf-font-stream PDF embedded font (sfnt) at offset 0x889B 15904 bytes