Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6a1566a0a342579…

MALICIOUS

PDF

120.6 KB Created: 2020-07-12 02:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: f83e04b02512ab6d47d8508dcbf8b24a SHA-1: 1f9971764076cba3dbf184fa99746e96deea4915 SHA-256: b6a1566a0a342579d79f22ac9a139cc51d36cd762e7b1e5f2f688a7b232cd6a2
234 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to domains designed for SEO manipulation and link farming. One critical heuristic identified a direct link to a known malicious redirector infrastructure at 'https://ttraff.ru/wb?keyword=norma%20oficial%20mexicana%20expediente%20clinico%20electronico%20pdf'. The ML classifier strongly supports the malicious nature of this PDF. The document body itself appears to be malformed or heavily obfuscated, but the presence of the malicious URL within it is a clear indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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/wb?keyword=norma%20oficial%20mexicana%20expediente%20clinico%20electronico%20pdf In PDF document text
    • http://files.appalachian-auditorium.org/uploads/1/3/1/4/131410812/8850719.pdfIn PDF document text
    • http://files.authorklmyers.com/uploads/1/3/1/1/131164275/nodane_limerumipiku_suliseratileza_dawidu.pdfIn PDF document text
    • http://files.nxtgenerationenergy.com/uploads/1/3/2/7/132740415/sodegebu.pdfIn PDF document text
    • http://files.hightechtintplus.com/uploads/1/3/2/3/132302973/47aff28564.pdfIn PDF document text
    • http://files.parentsforeczemaresearch.com/uploads/1/3/0/9/130969600/bipezavujiwilil_silarudu_didufefifo_rasezapopisopap.pdfIn PDF document text
    • http://files.willowwildedges.com/uploads/1/3/1/8/131856443/xukopiwome-tojazelapiz-kasivezobisu-sunezurawuse.pdfIn PDF document text
    • http://files.volgagermansportland.info/uploads/1/3/0/7/130738484/b7d9becfc16.pdfIn PDF document text
    • http://files.thefashionanalyst.com/uploads/1/3/1/3/131383624/wezunawe.pdfIn PDF document text
    • http://files.jelisajayrobinson.com/uploads/1/3/1/4/131437660/nupidigugugir_kezafixip_julaloli_jugowizudero.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://zulafavodu.files.wordpress.com/2020/07/38933588445.pdfIn PDF document text
    • https://levejaru304222751.files.wordpress.com/2020/06/tidofomaje.pdfIn PDF document text
    • https://zodefafubi.files.wordpress.com/2020/07/dedofubawabamebelusi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/4474/8950/files/mesilidumabukukef.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/4228/3432/files/42069503087.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/62654677968.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jobevemavesofidubuxiwi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/29426312843.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/5638/9528/files/databixerazezor.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/8643/8807/files/41472353708.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00018fbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18FBF 4948 bytes
SHA-256: d22d3bf3afe2e0565d00f8e4fb3d9b2c4208d31723941ca4e6eb870e1a5d3a86
font_01_sfnt_off0001a079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A079 17532 bytes
SHA-256: bc2dae7eb6d42da6ce9a0332bec4f9d3fb3a2c473060da461d14142f39c90de5