Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4d22b69748c6b96…

MALICIOUS

PDF

86.9 KB Created: 2021-09-03 21:46:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 227d5a2c450b74ae0f7e5a25de097cf1 SHA-1: 99f001729b4b7219a85c91b636b38b2f3385a031 SHA-256: a4d22b69748c6b966d518ccd7c94e9d23157372667b8ad7bc5c615d5bdb64168
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The PDF structure itself is also noted as having duplicate object bodies, which can be used for obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://raffaelecavazzoni.com/userfiles/files/dimujimetojufana.pdf In PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077358de853a---puvisudopewakonaxup.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/9426830043.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/gewut.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/51a20df376640ec7026a4927ac7087a1/5950147398.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c78744b8930---famumawazokaxurujeguxosol.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160735aa84952f---54730900685.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/tbli9oq4aluvl35jsc9tnq0bar/sekev.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1609c43e745680---nifowobifovalo.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1612195cc2238e---93016534270.pdfIn PDF document text
    • http://riviera.az/userfiles/file/4179958255.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/6d05823b8fd0694f2e0583e073b01ddb/78497523304.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5889b324ce---1079539961.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161307dd7064d4---pedojerorezewupawabekat.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/9444f436a77c45f79906bfe57a47bda0/15939760584.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/41344158630.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/vinawofifub.pdfIn PDF document text
    • http://logo4you.dk/userfiles/file/94787998427.pdfIn PDF document text
    • http://evolution-dev.com/file_media/file_image/file/64043041761.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/4d3b9908cf192d6d745a5d8709fda6b1/dotubiwusolagefejuwuxum.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/n7okii6cf0kl6k85v70ertabtt/nawunoxofiweberojur.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/60864080961.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/94456655614.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ec4ec1425---kedezevuxiwovejo.pdfIn PDF document text
    • http://poiskvod.ru/images/file/jejaxedu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=living+room+interior+design+catalogue+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9D 18884 bytes
SHA-256: 64c53559fb6c4bd255a8540ca8c909f7c78ed471cb41471beef3cf7b07bc6502
font_01_sfnt_off00011ba1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000133b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133B8 11088 bytes
SHA-256: 500a1a87c713d720352662387570bd0bb01b512f6aa2f35dfaa192953c42efda