Malicious PDF — malware analysis report

Static analysis result for SHA-256 a885cd409c89a7f9…

MALICIOUS

PDF

89.0 KB Created: 2021-06-27 21:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0f431fe2918f1064ed7fbe02950db17a SHA-1: f85d796b5b4437af3161eb8461fa13449c118b7b SHA-256: a885cd409c89a7f9be556845beb062148a2e97a0bf5fee4eb9db7aedb07467bb
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for SEO poisoning or to distribute further malware. No scripts were extracted, and the document body was unreadable binary data.

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://stef-nancy.fr/upload/document/rikejibixewuz.pdf
    • http://www.bufolari.com/public/immagini/file/jatomu.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3f1ec7c0e---dutapumeloxer.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0f789275d---24234753438.pdf
    • https://gangnampools.com/contents//files/wurotesumesuwiboziburu.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/161bea998aaaadb340d05922c89cfd4b/kodenapolagon.pdf
    • http://birnagarcollege.in/userfiles/file/30781223314.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/dcd3c2eb9f0551b823339917df5fc8c2/51952643446.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/hp7c1g9nqpjra4f1rqgi2cf1gu/papenopobaguweriwaganafox.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/adb9a1cc886e65af202d1b4efc5046e5/sagodabaxalezade.pdf
    • http://www.motionmantra.com/userfiles/files/novudoji.pdf
    • https://artlabjo.com/userfiles/file/9015320912.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb16106775---donenefulumutot.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c87651b362---56084347433.pdf
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/3ees9lcuo3ktnueuvksamisbuj/tanamumolotonutazemu.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606faa2682b29---buwepoxiw.pdf
    • https://bursac.net/userfiles/file/maranomugiked.pdf
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/talunigavaru.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/3gfn9hm7t3fb1l5go8eg91gdb7/10084433904.pdf
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/gisiwabilelemedewejifu.pdf
    • https://cavalier-hundezucht.ch/userfiles/file/13850615000.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c019ff840fe---vijupizumawuregofimuwoxuw.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c95d77aa68---87295565757.pdf
    • https://capecoralliving.com/media/file/velinotovemaxepokap.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077ab9738699---xosebunasusawomotalijes.pdf
    • https://csp-pub.com/stockages/files/zitiwuzuxerituv.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/4ge2p9tkg6qgdvml3lk61jotoc/53822322549.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+make+barn+in+minecraft
    • 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_off0000fac2.bin
fdc6f9ae99b45315b93fa7dbf8d00af4af6cd6a3299927ceabc384c086148fd8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC2 10592 bytes
font_01_sfnt_off000112f1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x112F1 16792 bytes
font_02_sfnt_off00012b03.bin
6de5dffc5244d821f61fd433b93cf6d9c94eb57dae5f56a8b6fff316142eac5b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B03 16756 bytes