Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bc241c6487d91d3…

MALICIOUS

PDF

34.6 KB Created: 2020-08-12 07:07:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1586e5110ab4463754a118e9a1825729 SHA-1: 0e9344c6ade2e9c5d47eb2e5847ec297dfc0f469 SHA-256: 8bc241c6487d91d34733cf5fad9a6e59e02b7694deaf6b14d5be2d7efb83d23e
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one identified as a malicious redirector and others pointing to a link farm. This suggests the primary purpose is to direct users to potentially harmful external websites. The ML classifier strongly supports the malicious nature of this PDF.

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=hallelujah+nuty+pdf+chomikuj
    • http://dewexiwim.happysnapsstudio.com/uploads/1/3/1/1/131163763/6fdfd1b460e6d8.pdf
    • http://files.syracusesheds.com/uploads/1/3/0/8/130813821/ea96d9a1.pdf
    • http://biwegaven.theheartofgolf.com/uploads/1/3/1/4/131407089/dujenut.pdf
    • http://files.inadocument.com/uploads/1/3/2/6/132696128/341013.pdf
    • http://xevuvodon.mariocostantinopace.com/uploads/1/3/2/8/132816202/nawukizuravuwetade.pdf
    • https://cdn.shopify.com/s/files/1/0435/4713/2068/files/42065978724.pdf
    • https://cdn.shopify.com/s/files/1/0430/8582/4164/files/90302543724.pdf
    • https://cdn.shopify.com/s/files/1/0429/5639/0559/files/rotebasunuguvurebelifimuz.pdf
    • https://cdn.shopify.com/s/files/1/0434/0239/5813/files/87240617279.pdf
    • https://cdn.shopify.com/s/files/1/0428/2925/0719/files/php_form_mailer_script.pdf
    • https://cdn.shopify.com/s/files/1/0429/4744/4899/files/84335081230.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kevesuladufutaniwor.pdf
    • https://cdn.shopify.com/s/files/1/0433/4046/4281/files/lamb_of_god_redneck.pdf
    • https://cdn.shopify.com/s/files/1/0430/6547/5229/files/48203752951.pdf
    • https://cdn.shopify.com/s/files/1/0434/3303/3877/files/38833957682.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_off00004950.bin
fac48e239730bd9573d94a9d43593c8b375ea4abf4ddbbcb6913531be8e75a25
pdf-font-stream PDF embedded font (sfnt) at offset 0x4950 5324 bytes
font_01_sfnt_off00005b4e.bin
46658c44862eeb712fe66af2f78fba1d276bd63fff21786b78cbded5e867eede
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B4E 10404 bytes