Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91db1caf3fb7440…

MALICIOUS

PDF

89.2 KB Created: 2021-06-30 02:34:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0646cc582124b5e7f3bbdb7e0ef2f11f SHA-1: 4a2e8422eee31bfbd78520bb909f82817d961715 SHA-256: a91db1caf3fb7440cc2d5dc88ff3f0e09e990d2a2b07ffd242f2c2c162d5a6de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The sample likely serves as a lure to direct users to compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://allytemp.ru/uplcv?utm_term=physics+for+engineers+by+giasuddin+pdf
    • https://www.swissfillon.com/wp-content/plugins/super-forms/uploads/php/files/9db5d795cf2c1e59ea483e1a78aee329/dirukez.pdf
    • http://diacritic.org/travel/app/webroot/img/files/53015176670.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16079f9d45fdaf---virerujesuweluda.pdf
    • http://dallapietamarchisio.it/userfiles/files/61144421353.pdf
    • https://alkalacarservice.com/public_html/userfiles/file/939802366.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/7b5c64b5d9e185514e2c2c10e4c09a78/7004078917.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/kh82evha1j2sbfntj8rs1ufaet/35518834465.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/7mvjitjb4shp4arpsuj9v6ln60/saxowiwifekeziwig.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/27d868c8da35dcced9c39edca7a488b5/fexeja.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a124bd93774---pobakiwedazir.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b82e2a4a9---devuzijamelobafulixu.pdf
    • http://medicapoland.pl/uploaded/file/xexawa.pdf
    • http://sitoad.com/bbqjoekey/files/202106140136299588.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a87c51b062c---tosariguralijoviwanegir.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/bcn6nj9c6ffvhm8sa6r9khi07k/zifolepoxamakezuburupeleg.pdf
    • http://azseal.net/uploads/userfiles/file/zidokifegamajoj.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/a19a006249d326391267f133bbc1c879/togelonoxufexepar.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/5bdbb59a8d10e20f5ff9fe2b996fb84a/wojalowakapetax.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/20e14eac796a6800903cffb0dc25737e/boxedadirifufup.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/0902128c7da82da8ec57728244df7241/budevo.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/3okbcm5q9dihe6cajiodtlsjn1/56913907095.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6987bd464---vaketonegusemuf.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607887a7f08d8---rakadifitulanufitedigag.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/0526249f5d2649d89abf5090de8e70cc/pagetonavamofumed.pdf
    • http://morgancountyoh.com/userimages/10101614778.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b46fede4f9b---51272178533.pdf
    • http://jhferry.com/data/fckeditor/file///10453809340.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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f42b.bin
1cc230393a14d0175ba22c30978024c6f9da6b667dc9adb1b3d225008c5dafb4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF42B 18540 bytes
font_01_sfnt_off000125b2.bin
bfb4eaae60ca8f435ba39f2c89833b8cd421309b1cd5d9e2150ebeee3e676234
pdf-font-stream PDF embedded font (sfnt) at offset 0x125B2 11108 bytes
font_02_sfnt_off00013f26.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F26 16792 bytes