Malicious PDF — malware analysis report

Static analysis result for SHA-256 b27aff9c63dc78e5…

MALICIOUS

PDF

96.6 KB Created: 2021-07-03 15:02:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 181f9374d6e3b90e604b2fe6e756cf39 SHA-1: 77b827609a632ae77309cdb67104be9b288c6d39 SHA-256: b27aff9c63dc78e52157e9841439f18e4708cbbd52620da119a3344f5e4f48ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the PDF structure strongly suggest it's used as a lure, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://coretry.ru/uplcv?utm_term=sales+manager+interview+questions
    • https://www.myosiaffiliate.com/199trust/img/file/10994533232.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b7a5332c6ff---76868776734.pdf
    • https://bestofbucerias.com/upload/file/joxofibifijegopukag.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8acdab1ba---zinosuxobesuvusuv.pdf
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/89q6sms533o1cvsnhhe459ahcu/mekunasikivegefemadata.pdf
    • http://hy-concrete.ru/d/files/10017071644.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/117cf011b415bb3a770c5de0384f6fcd/32550568375.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfae0e724f2---siwixexetawuropibigeze.pdf
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/04a5c689ffde6db2768ff17fa9175386/bigenulaxekakositebogatan.pdf
    • https://tonitomov.com/picture/file/11963085179.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/mbk20tn0r40lolfmiblt3ptd88/56998704619.pdf
    • http://www.euro-fly.eu/userfiles/files/waropubir.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/aj442tuj1rvoh8m5aedn3f4j9h/labifurugivozelo.pdf
    • http://ttccid.com/userfiles/files/vusuduzefa.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ddf8a0803---57163591313.pdf
    • https://mintowncoffee.net/uploads/images/files/57449461653.pdf
    • http://aivieksteslaivas.lv/userfiles/file/welaro.pdf
    • https://sharadsangam.org/UserFilesTwo/file/kopamixazob.pdf
    • http://americasbestmanassas.com/uploads/files/41095174005.pdf
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/a1b72ebb075f97de35d44d5e3929700d/pekujovazixemixafexa.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608d51aaac429---vivuradarijarodun.pdf
    • http://aeronautike.com/userfiles/file/11116537073.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a6b60a949---23742862784.pdf
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/1aefc12c000c482d3ddf35bb9357b751/mubivebazumizajamiwif.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_off000118ac.bin
e4877eaf7970230af917ea5553478d28ef323feedaac45c4b5c3848793b16941
pdf-font-stream PDF embedded font (sfnt) at offset 0x118AC 10924 bytes
font_01_sfnt_off000131ae.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x131AE 16792 bytes
font_02_sfnt_off000149c0.bin
7f971767e1d5fcaa1e6ffa740d0221ce1b137ed14a29e25009dd7ed09e6e1fce
pdf-font-stream PDF embedded font (sfnt) at offset 0x149C0 16796 bytes