Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d4f7d8bec401523…

MALICIOUS

PDF

42.1 KB Created: 2020-09-03 01:06:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c1e5375217c51d1088ed0dd9235c9852 SHA-1: e9102013fa786293063ef813124c097c275ea1ed SHA-256: 5d4f7d8bec401523149ae1bb8ecabccb6effd058cff084e2cc89199a5ae1a22f
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a lure for an 'andropen office apk' and includes a link to a redirector infrastructure. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' and the presence of numerous external PDF links indicate malicious intent. The document body, though heavily obfuscated, contains the primary malicious URL, suggesting the document's purpose is to trick the user into downloading a potentially malicious application.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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/wix?keyword=andropen+office+apk
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/debbe1_4d6f2b7c23a54c69b6d1765eec283d5c.pdf
    • https://static.usrfiles.com/ugd/b30cf0_dfced267158e440d9b4cd44bab1a38eb.pdf
    • https://static.usrfiles.com/ugd/8d57bd_ff14b912232644d495d0dae8733dab98.pdf
    • https://static.usrfiles.com/ugd/b8c837_21ad8ac7d4304e9da264adf9cb0aa49b.pdf
    • https://cdn.shopify.com/s/files/1/0430/0010/3073/files/bakiwemevawuvamupumux.pdf
    • https://cdn.shopify.com/s/files/1/0428/3911/3895/files/nemizemasomivibi.pdf
    • https://static.usrfiles.com/ugd/23e9be_1ffbc366852a4a97851b0ed9d850cee4.pdf
    • https://static.usrfiles.com/ugd/71fd01_a8601b40f10244a8ac5714aeb5e5cba3.pdf
    • https://static.usrfiles.com/ugd/9a242c_f61e45d222044db2af502ed6432250ed.pdf
    • https://cdn.shopify.com/s/files/1/0429/6186/2810/files/national_education_service.pdf
    • https://cdn.shopify.com/s/files/1/0450/9872/9625/files/hipoglucemiantes_orales.pdf
    • https://cdn.shopify.com/s/files/1/0431/1570/8573/files/30432574658.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006327.bin
fee834b0ddc844307efccf1ae2ca0f75021f9f096a5e4b77d43c4ea3c75a4825
pdf-font-stream PDF embedded font (sfnt) at offset 0x6327 4992 bytes
font_01_sfnt_off00007439.bin
cb207bc44ad52ecd1288d4ad4260525db3ede904a918d6948a8e6d5310e63641
pdf-font-stream PDF embedded font (sfnt) at offset 0x7439 12364 bytes