Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c76080ab4453479…

MALICIOUS

PDF

52.1 KB Created: 2020-07-17 04:44:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-07
MD5: cf69c7aa26fb686631dfb6a18cd896d4 SHA-1: 661f389add9e705e9d69c175269488dfce895708 SHA-256: 8c76080ab4453479f56550a8b0a5d9144fa46b91795a14bdc2b21af90e9a2633
234 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains numerous links designed to farm SEO traffic, directing users to a redirector URL which then points to other PDF files. The ML classifier strongly indicated maliciousness, and the presence of multiple external PDF links suggests an attempt to distribute further malicious content or phish users. No scripts were extracted, but the document's structure and link farm indicate a malicious intent to lure users to external resources.

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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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=video%20poker%20cheat%20sheet%20pdf In PDF document text
    • http://files.hiddendragonmartialartsacademy.com/uploads/1/3/0/7/130775539/3294151.pdfIn PDF document text
    • http://files.tinyfarmlabs.com/uploads/1/3/0/7/130776343/233182.pdfIn PDF document text
    • http://files.parsonsperiodpresentations.com/uploads/1/3/0/7/130739782/newazoj.pdfIn PDF document text
    • http://files.missionographer.com/uploads/1/3/0/8/130814907/jujelizulejotus.pdfIn PDF document text
    • http://files.judithgoldstonedesigns.com/uploads/1/3/1/4/131438423/3826532.pdfIn PDF document text
    • http://files.ryanleekk.com/uploads/1/3/1/3/131398573/bivaj-piwuj-foganun.pdfIn PDF document text
    • http://files.sarusfestival.org/uploads/1/3/1/4/131453894/3958547.pdfIn PDF document text
    • http://files.jadepublishing.org/uploads/1/3/1/6/131636584/7a0d98704.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://wapisamuvubu.files.wordpress.com/2020/06/sisapex.pdfIn PDF document text
    • https://xozigun417683795.files.wordpress.com/2020/07/takavamakolimeraranovidog.pdfIn PDF document text
    • https://ronefivuvan.files.wordpress.com/2020/06/telazitipurimunifu.pdfIn PDF document text
    • https://fujezarek.files.wordpress.com/2020/06/fadazikujele.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/1660/1249/files/wakevevesajirasenipaxij.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1661/8145/files/xelitesoxasamifumaku.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/5095/1066/files/75998153616.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/4858/1782/files/94775872328.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/pelezegagujagemubejapo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/rumifagekesodurelakalon.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/2290/1663/files/rofopabitozarexodezamis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/7120/1695/files/97665120230.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_off00008f96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8F96 4924 bytes
SHA-256: 16604841403a9e569d1f56d4283df25ad4292d220785f0a68766da9db21a5aa7
font_01_sfnt_off0000a066.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA066 10092 bytes
SHA-256: d9c1462c54b620207b418d6eadfd0de47cd8edcd7b0852f1adcefc960f1a312b