Malicious PDF — malware analysis report

Static analysis result for SHA-256 b64ce42ff6f05be3…

MALICIOUS

PDF

41.0 KB Created: 2020-08-04 13:25:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 179bdffeb36ae87c806b3feb4c6a2d0c SHA-1: 3d1960a9cf2d219c79001543c17d4126bd532ab9 SHA-256: b64ce42ff6f05be34751dc4b2c2ad9a7533fddd8390251d9fe5be6cc10c8ef6b
154 Risk Score

Malware Insights

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

The PDF document was flagged by a critical heuristic for linking to known malicious redirector infrastructure. It also contains a large number of SEO-optimized PDF links, suggesting a link farm or SEO poisoning attempt. The document body, though heavily obfuscated, contains text related to 'math worksheets' and the malicious URL, indicating a lure to drive traffic to malicious sites.

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/wb?keyword=math%20worksheets%20grade%201%20multiplication
    • http://files.xscriptsecurity.com/uploads/1/3/1/0/131070561/lusepovenawozo.pdf
    • http://files.sourmashstringband.com/uploads/1/3/2/6/132695516/9801390.pdf
    • http://files.spectrarte.com/uploads/1/3/1/0/131070678/7600965.pdf
    • http://files.lacostacanyontheatre.com/uploads/1/3/2/3/132303068/859558ebdaf76.pdf
    • http://files.maurerandstrange.com/uploads/1/3/1/8/131871467/jobigesu_dogojirafiji.pdf
    • https://cdn.shopify.com/s/files/1/0430/3772/0733/files/43810686932.pdf
    • https://cdn.shopify.com/s/files/1/0434/1009/6284/files/segekawakagaro.pdf
    • https://cdn.shopify.com/s/files/1/0430/6026/5117/files/26419762605.pdf
    • https://cdn.shopify.com/s/files/1/0432/3731/0626/files/zazagugegowez.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/lovukapovilelogitolosir.pdf
    • https://cdn.shopify.com/s/files/1/0431/6063/3504/files/tesan.pdf
    • https://cdn.shopify.com/s/files/1/0437/1811/5480/files/nimor.pdf
    • https://cdn.shopify.com/s/files/1/0433/0238/7867/files/8580774413.pdf
    • https://cdn.shopify.com/s/files/1/0437/7473/8581/files/24864200489.pdf
    • https://cdn.shopify.com/s/files/1/0432/8469/3160/files/59872306152.pdf
    • https://cdn.shopify.com/s/files/1/0434/9113/1557/files/91789868244.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_off00006096.bin
e74fd532a988aad23e6bd00bd6d930e12af9cf3ab43a84ad892e37f747602af6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6096 5700 bytes
font_01_sfnt_off000073f5.bin
6584ec1ca6ff79e66d37737a82a96f97f81d166ae6caff6a77652d123b7adbcb
pdf-font-stream PDF embedded font (sfnt) at offset 0x73F5 10264 bytes