Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6b657f39e84496d…

MALICIOUS

PDF

35.5 KB Created: 2020-08-03 22:03:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 080cc097be1724dd2d108d0dc14d9e0b SHA-1: 175cbdd01b4a10f608f6c489a13eab3e12b37617 SHA-256: d6b657f39e84496db7ee3e181bb34da422a8723512b855b12816bce91396a249
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external resources, including a known malicious redirector. The document body, though partially corrupted, suggests a lure related to 'definite and indefinite articles worksheets'. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK and PDF_SEO_LINK_FARM strongly indicate a malicious intent to redirect users to potentially harmful sites. The ML classifier also flagged this PDF with high confidence.

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=definite+and+indefinite+articles+worksheets+with+answers+pdf
    • http://files.pitch2script.com/uploads/1/3/0/9/130969855/tijitanu.pdf
    • http://janovaluk.jamieshumway.com/uploads/1/3/1/0/131070718/4f654.pdf
    • http://files.haskettconsults.com/uploads/1/3/1/0/131069950/tanuzu.pdf
    • https://cdn.shopify.com/s/files/1/0432/5651/2676/files/nusinofetasavokale.pdf
    • https://cdn.shopify.com/s/files/1/0430/9296/7581/files/zakim.pdf
    • https://cdn.shopify.com/s/files/1/0434/5341/5576/files/80197627248.pdf
    • https://cdn.shopify.com/s/files/1/0432/0247/8242/files/wovavadojakejuwebame.pdf
    • https://cdn.shopify.com/s/files/1/0431/3631/9639/files/66650683883.pdf
    • https://cdn.shopify.com/s/files/1/0437/3023/9642/files/temepezixefon.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/91960476686.pdf
    • https://cdn.shopify.com/s/files/1/0430/1471/7597/files/23635685201.pdf
    • https://cdn.shopify.com/s/files/1/0434/1802/6142/files/71783122914.pdf
    • https://cdn.shopify.com/s/files/1/0435/7485/3793/files/kubota_zd28_manual.pdf
    • https://cdn.shopify.com/s/files/1/0436/9865/1288/files/93448415504.pdf
    • https://cdn.shopify.com/s/files/1/0427/4959/1718/files/33539291183.pdf
    • https://cdn.shopify.com/s/files/1/0434/2729/9478/files/59361260275.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_off00004ca7.bin
efb98e4b07c0c21dbe1e8210925e4e3666898e95e93b7326db9fc5418833fe2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x4CA7 5396 bytes
font_01_sfnt_off00005f1b.bin
0bff850a9ac4e47a7f3e25a57f58580fbe977613596c1de2a3f6053d196d52e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F1B 9904 bytes