Malicious PDF — malware analysis report

Static analysis result for SHA-256 90f71e4105ea008d…

MALICIOUS

PDF

92.8 KB Created: 2021-06-27 23:32:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a987d86068a2502bc3f1ef76f75b5e9c SHA-1: e6b831ef164c330c48152f589ce1fdc938a0696b SHA-256: 90f71e4105ea008d14e692a2b7b57814d306cc329f40880ce5beb3ee5d0af3e3
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. It contains numerous URLs pointing to compromised WordPress sites, suggesting an attempt to lure users to malicious content. The PDF structure and embedded links are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/91c135146f51808dbbba99aac519664e/basekoxito.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b65c8041a96---18266375661.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/qfmf0qkktb23todh0mopf05pu3/409087550.pdf
    • http://atut-biuro.com/uploaded/file/4939665536.pdf
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/9c8403a8350739fa160b852831757ac3/55098593663.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba88353080---43006306156.pdf
    • http://dtcguild.org/clients/80367/File/55758875238.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/41b09d7ede95f98527b317b73896fb80/87053438421.pdf
    • http://jshtextile.com/UserFiles/file///37116569754.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/ptg311k1kabmr314fglcnlr506/piwazemujurulonafamokav.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd223d10a93---17873464444.pdf
    • https://bustotoronto.com/userfiles/file/nufusoxobofodulokuluxenop.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16093b236b57b1---60461799975.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/f21e6a59ee87ab631dccefeb5362d0b1/mixenowafazeratixifida.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae6f4c2905---69154298930.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/57af7e08f529402ff78274fdbef27fb5/mojaferuwogipu.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/ce04b55aa36e888402894ea698ceee5a/nelakej.pdf
    • http://gtlitalia.com/userfiles/files/bolipegep.pdf
    • http://whs1979.net/clients/65916/File/varuwibaz.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16072c786e81bd---pavamikomeneragijinakir.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/0i56lnpgml1ssk1lkviqjrf381/18188601968.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/16089939ae2c01---38974311908.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac52fa264d3---48273516809.pdf
    • http://www.urbanwaterways.info/files/sidipudedinatasubarakawo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=startup+financial+projections+example
    • 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_off000107b0.bin
02194176fcbc27b6ac458012ae72f15980d233a120b6e70d3c1a3224b9400793
pdf-font-stream PDF embedded font (sfnt) at offset 0x107B0 17024 bytes
font_01_sfnt_off0001342d.bin
255d64c5134c323d42fa99b47c77be4cf9e2cdae18a4a1934a8e794446a400f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1342D 11048 bytes
font_02_sfnt_off00014dd7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DD7 16792 bytes